Medicine and Health Sciences Commons^™

Expression Of Heme Oxygenase-1 In Thick Ascending Loop Of Henle Attenuates Angiotensin Ii-Dependent Hypertension, David E. Stec, Heather A. Drummond, Moneete U. Gousette, Megan V. Storm, Nader G. Abraham, Eva Csongradi

Nader G. Abraham

Kidney-specific induction of heme oxygenase-1 (HO-1) attenuates the development of angiotensin II (Ang II) -dependent hypertension, but the relative contribution of vascular versus tubular induction of HO-1 is unknown. To determine the specific contribution of thick ascending loop of Henle (TALH) -derived HO-1, we generated a transgenic mouse in which the uromodulin promoter controlled expression of human HO-1. Quantitative RT-PCR and confocal microscopy confirmed successful localization of the HO-1 transgene to TALH tubule segments. Medullary HO activity, but not cortical HO activity, was significantly higher in transgenic mice than control mice. Enhanced TALH HO-1 attenuated the hypertension induced by Ang …

Ho-1 Induction Improves The Type-1 Cardiorenal Syndrome In Mice With Impaired Angiotensin Ii–Induced Lymphocyte Activation, Sumit R. Monu, Paola Pesce, Komal Sodhi, Massimo Boldrin, Nitin Puri, Larisa Fedorova, David Sacerdoti, Stephen J. Peterson, Nader G. Abraham, Attallah Kappas

Nader G. Abraham

Type-1 cardiorenal syndrome, characterized by acute kidney dysfunction secondary to cardiac failure and renal arteriolar vasoconstriction, is mediated by the renin–angiotensin–aldosterone axis and sympathetic nervous system activation. Previous reports indicate that angiotensin II modulates immune function and causes recruitment and activation of T-lymphocytes. The goal of this study was to evaluate the effects of postischemic heart failure on renal morphology and circulation and the beneficial effects of heme oxygenase-1 (HO-1) induction in T-lymphocyte–suppressed severe combined immune deficiency (SCID) mice. Mice were divided into 4 groups: sham, myocardial infarction (MI), MI treated with an HO-1 inducer, cobalt protoporphyrin, and with or …

Mir-30b/30d Regulation Of Galnac Transferases Enhances Invasion And Immunosuppression During Metastasis, Avital Gaziel-Sovran, Miguel Segura, Raffaella Di Micco, Mary Collins, Douglas Hanniford, Eleazar De Miera, John Rakus, John Dankert, Shulian Shang, Robert Kerbel, Nina Bhardwaj, Yongzhao Shao, Farbod Darvishian, Jiri Zavadil, Adrian Erlebacher, Lara Mahal, Iman Osman, Eva Hernando

John F. Rakus

To metastasize, a tumor cell must acquire abilities such as the capacity to colonize new tissue and evade immune surveillance. Recent evidence suggests that microRNAs can promote the evolution of malignant behaviors by regulating multiple targets. We performed a microRNA analysis of human melanoma, a highly invasive cancer, and found that miR-30b/30d upregulation correlates with stage, metastatic potential, shorter time to recurrence, and reduced overall survival. Ectopic expression of miR-30b/30d promoted the metastatic behavior of melanoma cells by directly targeting the GalNAc transferase GALNT7, resulted in increased synthesis of the immunosuppressive cytokine IL-10, and reduced immune cell activation and recruitment. …

A Comparison Of Four Electrical Stimulation Types On Staphylococcus Aureus Growth In Vitro, Harold Merriman, Chris Hegyi, Cheryl Albright-Overton, John Carlos, Robert Putnam, Janet Mulcare

Harold L. Merriman

We evaluated the efficacy of common electrical stimulation (ES) types on bacterial growth in vitro using clinically relevant conditions. Four types of ES-continuous microamperage direct current (µADC), high-voltage pulsed current (HVPC), low-voltage monophasic milliamperage pulsed current (LVMmAPC), and low-voltage biphasic milliamperage pulsed current (LVBmAPC)-were each applied to a separate set of culture plates containing Staphylococcus aureus for 1 h at 37 °C on 3 consecutive days. After ES treatment, the zone of inhibition surrounding each electrode was measured. Zone of inhibition measurements showed a significant inhibitory effect for continuous µADC and HVPC (p < 0.05), but not for LVMmAPC and LVBmAPC. …

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

Anatoly Kiyatkin

BACKGROUND: Cell-to-cell variability in protein expression can be large, and its propagation through signaling networks affects biological outcomes. Here, we apply deterministic and probabilistic models and biochemical measurements to study how network topologies and cell-to-cell protein abundance variations interact to shape signaling responses. RESULTS: We observe bimodal distributions of extracellular signal-regulated kinase (ERK) responses to epidermal growth factor (EGF) stimulation, which are generally thought to indicate bistable or ultrasensitive signaling behavior in single cells. Surprisingly, we find that a simple MAPK/ERK-cascade model with negative feedback that displays graded, analog ERK responses at a single cell level can explain the experimentally …

Iron-Induced Cardiac Damage: Role Of Apoptosis And Deferasirox Intervention, Yeling Wang, Miaozong Wu, Rabaa Al-Rousan, Hua Liu, Jacqueline Fannin, Satyanarayana Paturi, Ravi Arvapalli, Anjaiah Katta, Sunil Kakarla, Kevin Rice, William Triest, Eric Blough

Kevin M Rice

Excess cardiac iron levels are associated with cardiac damage and can result in increased morbidity and mortality. Here, we hypothesize that elevations in tissue iron can activate caspase-dependent signaling, which leads to increased cardiac apoptosis and fibrosis, and that these alterations can be attenuated by iron chelation. Using an iron-overloaded gerbil model, we show that increased cardiac iron is associated with reduced activation of Akt (Ser473 and Thr308), diminished phosphorylation of the proapoptotic regulator Bad (Ser136), and an increased Bax/Bcl-2 ratio. These iron-overload-induced alterations in Akt/Bad phosphorylation and Bax/Bcl-2 ratio were coupled with increased activation of the downstream caspase-9 (40/38- …

Gadd45Γ Mediates The Activation Of The P38 And Jnk Map Kinase Pathways And Cytokine Production In Effector Th1 Cells, Binfeng Lu, Hong Yu, Chi-Wing Chow, Baiyong Li, Wei-Ping Zeng, Roger Davis, Richard Flavell

Wei-ping Zeng

The p38 and JNK stress-activated MAPK signal transduction pathways are activated by T cell receptor (TCR) signaling and are required for IFN-γ production by T_H1 effector cells. Here, we show that the expression of GADD45γ is induced during T cell activation and that the level of expression is higher in T_H1 cells than in T_H2 cells. T_H1 cells from GADD45γ^−/− mice are severely compromised in their abilities to activate p38 and JNK in response to TCR signaling, produce much less IFN-γ upon restimulation, and are deficient in activation-induced cell death (AICD). …

Dietary Canola Oil Suppressed Growth Of Implanted Mda-Mb 231 Human Breast Tumors In Nude Mice, W. Hardman

Elaine Hardman Ph.D.

Long chain omega 3 (n-3) fatty acids, eicosapentaenoic (EPA) and/or docosahexaenoic acid (DHA), have been shown to suppress growth of most cancer cells. In vivo, alpha linolenic acid (ALA, 18:3n-3) can be converted to EPA or DHA. We hypothesized that substituting canola oil (10% ALA) for the corn oil (1% ALA) in the diet of cancer bearing mice would slow tumor growth by increasing n-3 fatty acids in the diet. Sixty nude mice received MDA-MB 231 human breast cancer cells and were fed a diet containing 8% w/w corn oil until the mean tumor volume was 60 mm 3 . …

Vitamin A (Retinoids) Regulation Of Mouse Melanoma Growth And Differentiation, Richard Niles

Richard M Niles

The incidence of melanoma is rapidly increasing in the U.S. population. At the present, there is no effective chemotherapy against invasive melanoma. At our laboratory, we have been studying retinoic acid (RA)-induced growth arrest and differentiation in the B16 murine melanoma cell model. Several immediate-early gene targets of RA were identified by gene arrays. In one of these genes, T-box binding protein-2 (Tbx-2), an RA response element, was identified in the promoter region that mediates the RA responsiveness of this gene. RA also induces a sixfold to eightfold increase in protein kinase C (PKC)α RNA and protein. This gene is …

Effect Of Aging On Cellular Mechanotransduction, Miaozong Wu, Jacqueline Fannin, Kevin Rice, Bin Wang, Eric Blough

Eric Blough

Aging is becoming a critical heath care issue and a burgeoning economic burden on society. Mechanotransduction is the ability of the cell to sense, process, and respond to mechanical stimuli and is an important regulator of physiologic function that has been found to play a role in regulating gene expression, protein synthesis, cell differentiation, tissue growth, and most recently, the pathophysiology of disease. Here we will review some of the recent findings of this field and attempt, where possible, to present changes in mechanotransduction that are associated with the aging process in several selected physiological systems, including musculoskeletal, cardiovascular, neuronal, …

Iron-Induced Cardiac Damage: Role Of Apoptosis And Deferasirox Intervention, Yeling Wang, Miaozong Wu, Rabaa Al-Rousan, Hua Liu, Jacqueline Fannin, Satyanarayana Paturi, Ravi Arvapalli, Anjaiah Katta, Sunil Kakarla, Kevin Rice, William Triest, Eric Blough

Ravi K. Arvapalli

Excess cardiac iron levels are associated with cardiac damage and can result in increased morbidity and mortality. Here, we hypothesize that elevations in tissue iron can activate caspase-dependent signaling, which leads to increased cardiac apoptosis and fibrosis, and that these alterations can be attenuated by iron chelation. Using an iron-overloaded gerbil model, we show that increased cardiac iron is associated with reduced activation of Akt (Ser473 and Thr308), diminished phosphorylation of the proapoptotic regulator Bad (Ser136), and an increased Bax/Bcl-2 ratio. These iron-overload-induced alterations in Akt/Bad phosphorylation and Bax/Bcl-2 ratio were coupled with increased activation of the downstream caspase-9 (40/38- …

Iron-Induced Cardiac Damage: Role Of Apoptosis And Deferasirox Intervention, Yeling Wang, Miaozong Wu, Rabaa Al-Rousan, Hua Liu, Jacqueline Fannin, Satyanarayana Paturi, Ravi Arvapalli, Anjaiah Katta, Sunil Kakarla, Kevin Rice, William Triest, Eric Blough

Eric Blough

Excess cardiac iron levels are associated with cardiac damage and can result in increased morbidity and mortality. Here, we hypothesize that elevations in tissue iron can activate caspase-dependent signaling, which leads to increased cardiac apoptosis and fibrosis, and that these alterations can be attenuated by iron chelation. Using an iron-overloaded gerbil model, we show that increased cardiac iron is associated with reduced activation of Akt (Ser473 and Thr308), diminished phosphorylation of the proapoptotic regulator Bad (Ser136), and an increased Bax/Bcl-2 ratio. These iron-overload-induced alterations in Akt/Bad phosphorylation and Bax/Bcl-2 ratio were coupled with increased activation of the downstream caspase-9 (40/38- …

Il-7 Is A Critical Factor In Modulating Lesion Development In Skn-Directed Autoimmunity, Pamela Staton, A. Carpenter, Susan Jackman

A. Betts Carpenter

In a murine model of autoimmunity targeted against the epidermal cell Ags, Skn, adoptive transfer of Skn-immune T cells to immunosuppressed recipients elicits skin lesions in areas of mild epidermal trauma. In this study, we examined peripheral regulation of Skn-induced autoreactivity disrupted by rendering the mice immunoincompetent. We found that regulation of Skn-directed autoimmunity was restored by cotransfer of normal syngeneic spleen cells at twice the concentration of Skn-immune cells and was evidenced by significantly reduced lesion severity by days 5–7 post-cotransfer compared with animals given injections of Skn-immune cells alone. Enrichment and depletion of normal CD4 or CD8 spleen …

Mg624, An A7-Nachr Antagonist, Inhibits Angiogenesis Via The Egr-1/Fgf2 Pathway, Kathleen Brown, Jamie Lau, Aaron Dom, Theodore Witte, Haitao Luo, Clayton Crabtree, Yashoni Shah, Brandon Shiflett, Aileen Marcelo, Nancy Proper, W. Hardman, Richard Egleton, Yi Chen, Elsa Mangiarua, Piyali Dasgupta

Nancy A. Proper

Small cell lung cancer (SCLC) demonstrates a strong etiological association with smoking. Although cigarette smoke is a mixture of about 4,000 compounds, nicotine is the addictive component of cigarette smoke. Several convergent studies have shown that nicotine promotes angiogenesis in lung cancers via the α7-nicotinic acetylcholine receptor (α7-nAChR) on endothelial cells. Therefore, we conjectured that α7-nAChR antagonists may attenuate nicotine-induced angiogenesis and be useful for the treatment of human SCLC. For the first time, our study explores the anti-angiogenic activity of MG624, a small-molecule α7-nAChR antagonist, in several experimental models of angiogenesis. We observed that MG624 potently suppressed the proliferation …

Mg624, An A7-Nachr Antagonist, Inhibits Angiogenesis Via The Egr-1/Fgf2 Pathway, Kathleen Brown, Jamie Lau, Aaron Dom, Theodore Witte, Haitao Luo, Clayton Crabtree, Yashoni Shah, Brandon Shiflett, Aileen Marcelo, Nancy Proper, W. Hardman, Richard Egleton, Yi Chen, Elsa Mangiarua, Piyali Dasgupta

Jamie K. Lau

Small cell lung cancer (SCLC) demonstrates a strong etiological association with smoking. Although cigarette smoke is a mixture of about 4,000 compounds, nicotine is the addictive component of cigarette smoke. Several convergent studies have shown that nicotine promotes angiogenesis in lung cancers via the α7-nicotinic acetylcholine receptor (α7-nAChR) on endothelial cells. Therefore, we conjectured that α7-nAChR antagonists may attenuate nicotine-induced angiogenesis and be useful for the treatment of human SCLC. For the first time, our study explores the anti-angiogenic activity of MG624, a small-molecule α7-nAChR antagonist, in several experimental models of angiogenesis. We observed that MG624 potently suppressed the proliferation …

Silencing And Re-Expression Of Retinoic Acid Receptor Beta2 In Human Melanoma, Jun Fan, Linda Eastham, Melinda Varney, Adam Hall, Nicolas Adkins, Vincent Sollars, Philippe Georgel, Richard Niles

Linda L. Eastham

Many melanoma cells are resistant to the anti-proliferative effect of all trans retinoic acid (ATRA). Retinoic Acid Receptor-β2 (RAR-β2) mediates the ATRA growth inhibition. We found a correlation between the anti-proliferative activity of ATRA and expression of RAR-β2. There was not a strict correlation between DNA methylation of RAR-β gene and its expression. There was no difference in global and RARβ specific nucleosome repeat length (NRL) in melanoma and melanocytes or between control and ATRA treated cells. Pan-acetylation of H3 and H4 within the RAR-β gene promoter was higher in cells expressing RAR-β2. All trans retinoic acid treatment of …

Pparα/Γ Expression And Activity In Mouse And Human Melanocytes And Melanoma Cells, Linda Eastham, Caroline Mills, Richard Niles

Linda L. Eastham

Purpose. We examined the expression of PPARs and the effects of PPARα and PPARγ agonists on growth of mouse and human melanocytes and melanoma cells.

Methods. PPARα,β, and PPARγ mRNA qualitative expression in melan-a mouse melanocytes, B16 mouse melanoma, human melanocytes, and A375 and SK-mel28 human melanoma cells was determined by RT-PCR, while quantitative PPARα mRNA levels were determined by QuantiGene assay. PPARα and PPARγ protein was assessed by Western blotting. The effect of natural and synthetic PPAR ligands on cell growth was determined by either hemocytometer counting or crystal violet assay. PPAR transcriptional activity was determined by a PPRE-reporter …

Silencing And Re-Expression Of Retinoic Acid Receptor Beta2 In Human Melanoma, Jun Fan, Linda Eastham, Melinda Varney, Adam Hall, Nicolas Adkins, Vincent Sollars, Philippe Georgel, Richard Niles

Jun Fan

Many melanoma cells are resistant to the anti-proliferative effect of all trans retinoic acid (ATRA). Retinoic Acid Receptor-β2 (RAR-β2) mediates the ATRA growth inhibition. We found a correlation between the anti-proliferative activity of ATRA and expression of RAR-β2. There was not a strict correlation between DNA methylation of RAR-β gene and its expression. There was no difference in global and RARβ specific nucleosome repeat length (NRL) in melanoma and melanocytes or between control and ATRA treated cells. Pan-acetylation of H3 and H4 within the RAR-β gene promoter was higher in cells expressing RAR-β2. All trans retinoic acid treatment of …

Il-7 Is A Critical Factor In Modulating Lesion Development In Skn-Directed Autoimmunity, Pamela Staton, A. Carpenter, Susan Jackman

Susan H. Jackman

In a murine model of autoimmunity targeted against the epidermal cell Ags, Skn, adoptive transfer of Skn-immune T cells to immunosuppressed recipients elicits skin lesions in areas of mild epidermal trauma. In this study, we examined peripheral regulation of Skn-induced autoreactivity disrupted by rendering the mice immunoincompetent. We found that regulation of Skn-directed autoimmunity was restored by cotransfer of normal syngeneic spleen cells at twice the concentration of Skn-immune cells and was evidenced by significantly reduced lesion severity by days 5–7 post-cotransfer compared with animals given injections of Skn-immune cells alone. Enrichment and depletion of normal CD4 or CD8 spleen …

Mg624, An A7-Nachr Antagonist, Inhibits Angiogenesis Via The Egr-1/Fgf2 Pathway, Kathleen Brown, Jamie Lau, Aaron Dom, Theodore Witte, Haitao Luo, Clayton Crabtree, Yashoni Shah, Brandon Shiflett, Aileen Marcelo, Nancy Proper, W. Hardman, Richard Egleton, Yi Chen, Elsa Mangiarua, Piyali Dasgupta

Elsa I. Mangiarua

Small cell lung cancer (SCLC) demonstrates a strong etiological association with smoking. Although cigarette smoke is a mixture of about 4,000 compounds, nicotine is the addictive component of cigarette smoke. Several convergent studies have shown that nicotine promotes angiogenesis in lung cancers via the α7-nicotinic acetylcholine receptor (α7-nAChR) on endothelial cells. Therefore, we conjectured that α7-nAChR antagonists may attenuate nicotine-induced angiogenesis and be useful for the treatment of human SCLC. For the first time, our study explores the anti-angiogenic activity of MG624, a small-molecule α7-nAChR antagonist, in several experimental models of angiogenesis. We observed that MG624 potently suppressed the proliferation …

Il-7 Is A Critical Factor In Modulating Lesion Development In Skn-Directed Autoimmunity, Pamela Staton, A. Carpenter, Susan Jackman

Pamela J. Staton

In a murine model of autoimmunity targeted against the epidermal cell Ags, Skn, adoptive transfer of Skn-immune T cells to immunosuppressed recipients elicits skin lesions in areas of mild epidermal trauma. In this study, we examined peripheral regulation of Skn-induced autoreactivity disrupted by rendering the mice immunoincompetent. We found that regulation of Skn-directed autoimmunity was restored by cotransfer of normal syngeneic spleen cells at twice the concentration of Skn-immune cells and was evidenced by significantly reduced lesion severity by days 5–7 post-cotransfer compared with animals given injections of Skn-immune cells alone. Enrichment and depletion of normal CD4 or CD8 spleen …

Mg624, An A7-Nachr Antagonist, Inhibits Angiogenesis Via The Egr-1/Fgf2 Pathway, Kathleen Brown, Jamie Lau, Aaron Dom, Theodore Witte, Haitao Luo, Clayton Crabtree, Yashoni Shah, Brandon Shiflett, Aileen Marcelo, Nancy Proper, W. Hardman, Richard Egleton, Yi Chen, Elsa Mangiarua, Piyali Dasgupta

Richard D. Egleton

Small cell lung cancer (SCLC) demonstrates a strong etiological association with smoking. Although cigarette smoke is a mixture of about 4,000 compounds, nicotine is the addictive component of cigarette smoke. Several convergent studies have shown that nicotine promotes angiogenesis in lung cancers via the α7-nicotinic acetylcholine receptor (α7-nAChR) on endothelial cells. Therefore, we conjectured that α7-nAChR antagonists may attenuate nicotine-induced angiogenesis and be useful for the treatment of human SCLC. For the first time, our study explores the anti-angiogenic activity of MG624, a small-molecule α7-nAChR antagonist, in several experimental models of angiogenesis. We observed that MG624 potently suppressed the proliferation …

Mg624, An A7-Nachr Antagonist, Inhibits Angiogenesis Via The Egr-1/Fgf2 Pathway, Kathleen Brown, Jamie Lau, Aaron Dom, Theodore Witte, Haitao Luo, Clayton Crabtree, Yashoni Shah, Brandon Shiflett, Aileen Marcelo, Nancy Proper, W. Hardman, Richard Egleton, Yi Chen, Elsa Mangiarua, Piyali Dasgupta

Piyali Dasgupta

Small cell lung cancer (SCLC) demonstrates a strong etiological association with smoking. Although cigarette smoke is a mixture of about 4,000 compounds, nicotine is the addictive component of cigarette smoke. Several convergent studies have shown that nicotine promotes angiogenesis in lung cancers via the α7-nicotinic acetylcholine receptor (α7-nAChR) on endothelial cells. Therefore, we conjectured that α7-nAChR antagonists may attenuate nicotine-induced angiogenesis and be useful for the treatment of human SCLC. For the first time, our study explores the anti-angiogenic activity of MG624, a small-molecule α7-nAChR antagonist, in several experimental models of angiogenesis. We observed that MG624 potently suppressed the proliferation …

Effect Of Dna Damage On Pcr Amplification Efficiency With The Relative Threshold Cycle Method, Jan Sikorsky, Donald Primerano, Terry Fenger, James Denvir

James Denvir

Polymerase stop assays used to quantify DNA damage assume that single lesions are sufficient to block polymerase progression. To test the effect of specific lesions on PCR amplification efficiency, we amplified synthetic 90 base oligonucleotides containing normal or modified DNA bases using real-time PCR and determined the relative threshold cycle amplification efficiency of each template. We found that while the amplification efficiencies of templates containing a single 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) were not significantly perturbed, the presence of a single 8-oxo-7,8-dihydro-2′-deoxyadenosine, abasic site, or a cis–syn thymidine dimer dramatically reduced amplification efficiency. In addition, while templates containing two 8-oxodGs separated by 13 …

Global Analysis Of Gene Expression Changes During Retinoic Acid-Induced Growth Arrest And Differentiation Of Melanoma: Comparison To Differentially Expressed Genes In Melanocytes Vs Melanoma, Mary Estler, Goran Boskovic, James Denvir, Sarah Miles, Donald Primerano, Richard Niles

James Denvir

BACKGROUND: The incidence of malignant melanoma has significantly increased over the last decade. Some of these malignancies are susceptible to the growth inhibitory and pro-differentiating effects of all-trans-retinoic acid (RA). The molecular changes responsible for the biological activity of RA in melanoma are not well understood. RESULTS: In an analysis of sequential global gene expression changes during a 4-48 h RA treatment of B16 mouse melanoma cells, we found that RA increased the expression of 757 genes and decreased the expression of 737 genes. We also compared the gene expression profile (no RA treatment) between non-malignant melan-a mouse melanocytes and …

Silencing And Re-Expression Of Retinoic Acid Receptor Beta2 In Human Melanoma, Jun Fan, Linda Eastham, Melinda Varney, Adam Hall, Nicolas Adkins, Vincent Sollars, Philippe Georgel, Richard Niles

Philippe T. Georgel

Many melanoma cells are resistant to the anti-proliferative effect of all trans retinoic acid (ATRA). Retinoic Acid Receptor-β2 (RAR-β2) mediates the ATRA growth inhibition. We found a correlation between the anti-proliferative activity of ATRA and expression of RAR-β2. There was not a strict correlation between DNA methylation of RAR-β gene and its expression. There was no difference in global and RARβ specific nucleosome repeat length (NRL) in melanoma and melanocytes or between control and ATRA treated cells. Pan-acetylation of H3 and H4 within the RAR-β gene promoter was higher in cells expressing RAR-β2. All trans retinoic acid treatment of …

Effect Of Dna Damage On Pcr Amplification Efficiency With The Relative Threshold Cycle Method, Jan Sikorsky, Donald Primerano, Terry Fenger, James Denvir

Terry W. Fenger

Polymerase stop assays used to quantify DNA damage assume that single lesions are sufficient to block polymerase progression. To test the effect of specific lesions on PCR amplification efficiency, we amplified synthetic 90 base oligonucleotides containing normal or modified DNA bases using real-time PCR and determined the relative threshold cycle amplification efficiency of each template. We found that while the amplification efficiencies of templates containing a single 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) were not significantly perturbed, the presence of a single 8-oxo-7,8-dihydro-2′-deoxyadenosine, abasic site, or a cis–syn thymidine dimer dramatically reduced amplification efficiency. In addition, while templates containing two 8-oxodGs separated by 13 …

Endothelial Cell Pseudopods And Angiogenesis Of Breast Cancer Tumors, Ivan Cameron, Nicholas Short, Luzhe Sun, W. Hardman

Elaine Hardman Ph.D.

Background A neoplastic tumor cannot grow beyond a millimeter or so in diameter without recruitment of endothelial cells and new blood vessels to supply nutrition and oxygen for tumor cell survival. This study was designed to investigate formation of new blood vessels within a human growing breast cancer tumor model (MDA MB231 in mammary fat pad of nude female mouse). Once the tumor grew to 35 mm3, it developed a well-vascularized capsule. Histological sections of tumors greater than 35 mm3were stained with PAS, with CD-31 antibody (an endothelial cell maker), or with hypoxia inducible factor 1α antibody (HIF). The extent …

Mg624, An A7-Nachr Antagonist, Inhibits Angiogenesis Via The Egr-1/Fgf2 Pathway, Kathleen Brown, Jamie Lau, Aaron Dom, Theodore Witte, Haitao Luo, Clayton Crabtree, Yashoni Shah, Brandon Shiflett, Aileen Marcelo, Nancy Proper, W. Hardman, Richard Egleton, Yi Chen, Elsa Mangiarua, Piyali Dasgupta

Elaine Hardman Ph.D.

Small cell lung cancer (SCLC) demonstrates a strong etiological association with smoking. Although cigarette smoke is a mixture of about 4,000 compounds, nicotine is the addictive component of cigarette smoke. Several convergent studies have shown that nicotine promotes angiogenesis in lung cancers via the α7-nicotinic acetylcholine receptor (α7-nAChR) on endothelial cells. Therefore, we conjectured that α7-nAChR antagonists may attenuate nicotine-induced angiogenesis and be useful for the treatment of human SCLC. For the first time, our study explores the anti-angiogenic activity of MG624, a small-molecule α7-nAChR antagonist, in several experimental models of angiogenesis. We observed that MG624 potently suppressed the proliferation …

Differential Regulation Of Osteoblast Activity By Th Cell Subsets Mediated By Parathyroid Hormone And Ifn-, Nathan Young, Natallia Mikhalkevich, Ying Yan, Di Chen, Wei-Ping Zeng

Wei-ping Zeng

Bone loss is a typical pathological feature of chronic inflammatory bone diseases including rheumatoid arthritis, in which CD4 effector T cells play critical roles. We found that activated mouse Th2 and not Th1 cells produced the parathyroid hormone (PTH). Unlike in the parathyroid cells, PTH expression in Th2 cells was not regulated by the fluctuation of calcium level, but rather it required the full activation of the T cells. Although PTH was expressed in immature Th2 cells, and its receptor was transiently expressed during Th1 and Th2 cell differentiation, PTH did not significantly affect the outcome of the differentiation. In …