Cell and Developmental Biology Commons^™

Ecog-Acrin (E4805) Randomized Phase Ii Study To Determine The Effect Of 2 Different Doses Of Aflibercept In Patients With Metastatic Renal Cell Carcinoma, Roberto Pili, Opeyemi Jegede, Michael A. Carducci, Judith Manola, David L. Groteluschen, Leonard L. Appleman, Glenn Liu, James C. Shanks, Shaker R. Dakhil, Janice Dutcher, Robert S. Dipaola

Internal Medicine Faculty Publications

Background—Aflibercept is a recombinantly-produced fusion protein that has potent anti-VEGF activity. We tested whether aflibercept has clinical activity in clear cell renal cell carcinoma (ccRCC). The recommended Phase 2 dose was 4 mg/kg but several patients treated at 1 mg/kg demonstrated prolonged progression-free survival (PFS). We therefore tested both doses in a parallel group randomized trial.

Methods—Eligible patients (pts) had histologically confirmed advanced or metastatic ccRCC and previous treatments including prior exposure to a VEGF RTKI. Patients received aflibercept (either 1 mg/kg or 4 mg/kg) day 1 of a 14-day cycle until progression. Patients randomized to 1 mg/kg …

Nanoparticle Delivery Of Mir-34a Eradicates Long-Term-Cultured Breast Cancer Stem Cells Via Targeting C22orf28 Directly, Xiaoti Lin, Weiyu Chen, Fengqin Wei, Binhua P. Zhou, Mien-Chie Hung, Xiaoming Xie

Molecular and Cellular Biochemistry Faculty Publications

Rationale: Cancer stem cells (CSCs) have been implicated as the seeds of therapeutic resistance and metastasis, due to their unique abilities of self-renew, wide differentiation potentials and resistance to most conventional therapies. It is a proactive strategy for cancer therapy to eradicate CSCs. Methods: Tumor tissue-derived breast CSCs (BCSC), including XM322 and XM607, were isolated by fluorescence-activated cell sorting (FACS); while cell line-derived BCSC, including MDA-MB-231.SC and MCF-7.SC, were purified by magnetic-activated cell sorting (MACS). Analyses of microRNA and mRNA expression array profiles were performed in multiple breast cell lines. The mentioned nanoparticles were constructed following the standard molecular cloning …

Pleiotropy Of Genetic Variants On Obesity And Smoking Phenotypes: Results From The Oncoarray Project Of The International Lung Cancer Consortium, Tao Wang, Jee-Young Moon, Yiqun Wu, Christopher I. Amos, Rayjean J. Hung, Adonina Tardon, Angeline Andrew, Chu Chen, David C. Christiani, Demetrios Albanes, Erik H. F. M. Van Der Heijden, Eric Duell, Gadi Rennert, Gary Goodman, Geoffrey Liu, James D. Mckay, Jian-Min Yuan, John K. Field, Jonas Manjer, Kjell Grankvist, Lambertus A. Kiemeney, Loic Le Marchand, M. Dawn Teare, Matthew B. Schabath, Mattias Johansson, Melinda C. Aldrich, Michael Davies, Mikael Johansson, Ming-Sound Tsao, Neil Caporaso, Susanne Arnold

Internal Medicine Faculty Publications

Obesity and cigarette smoking are correlated through complex relationships. Common genetic causes may contribute to these correlations. In this study, we selected 241 loci potentially associated with body mass index (BMI) based on the Genetic Investigation of ANthropometric Traits (GIANT) consortium data and calculated a BMI genetic risk score (BMI-GRS) for 17,037 individuals of European descent from the Oncoarray Project of the International Lung Cancer Consortium (ILCCO). Smokers had a significantly higher BMI-GRS than never-smokers (p = 0.016 and 0.010 before and after adjustment for BMI, respectively). The BMI-GRS was also positively correlated with pack-years of smoking (p < 0.001) in smokers. Based on causal network inference analyses, seven and five of 241 SNPs were classified to pleiotropic models for BMI/smoking status and BMI/pack-years, respectively. Among them, three and four SNPs associated with smoking status and pack-years (p < 0.05), respectively, were followed up in the ever-smoking data of the Tobacco, Alcohol and Genetics (TAG) consortium. Among these seven candidate SNPs, one SNP (rs11030104, BDNF) …

Probing The Metabolic Phenotype Of Breast Cancer Cells By Multiple Tracer Stable Isotope Resolved Metabolomics, Andrew N. Lane, Julie Tan, Yali Wang, Jun Yan, Richard M. Higashi, Teresa W. -M. Fan

Center for Environmental and Systems Biochemistry Faculty Publications

Breast cancers vary by their origin and specific set of genetic lesions, which gives rise to distinct phenotypes and differential response to targeted and untargeted chemotherapies. To explore the functional differences of different breast cell types, we performed Stable Isotope Resolved Metabolomics (SIRM) studies of one primary breast (HMEC) and three breast cancer cells (MCF-7, MDAMB-231, and ZR75-1) having distinct genotypes and growth characteristics, using ¹³C₆-glucose, ¹³C-1+2-glucose, ¹³C₅,¹⁵N₂-Gln, ¹³C₃-glycerol, and ¹³C₈-octanoate as tracers. These tracers were designed to probe the central energy producing …

Multimodality Therapy Improves Survival In Intramedullary Spinal Cord Metastasis Of Lung Primary, Hayder Saeed, Reema Patel, Jigisha Thakkar, Lames Hamoodi, Li Chen, John L. Villano

Internal Medicine Faculty Publications

Background: Most metastatic spinal cord lesions are located either in the intradural, extramedullary, or in the epidural compartments. Intramedullary spinal cord metastasis (ISCM) is a rare central nervous system spread of cancer. The aim of this report was to evaluate ISCM in the published literature.

Methods: A literature review of PubMed from 1960 to 2016 was undertaken for the publications having demographic, clinical, histological, and outcome data.

Results: A total of 59 relevant papers were identified, showing 128 cases of intramedullary metastasis from lung cancer. The incidence of lung cancer as the primary malignancy with intramedullary metastasis was 56%. The …

Abl Kinase Regulation By Braf/Erk And Cooperation With Akt In Melanoma, Aditi Jain, Rakshamani Tripathi, Courtney P. Turpin, Chi Wang, Rina Plattner

Pharmacology and Nutritional Sciences Faculty Publications

The melanoma incidence continues to increase, and the disease remains incurable for many due to its metastatic nature and high rate of therapeutic resistance. In particular, melanomas harboring BRAF^V600E and PTEN mutations often are resistant to current therapies, including BRAF inhibitors (BRAFi) and immune checkpoint inhibitors. Abl kinases (Abl/Arg) are activated in melanomas and drive progression; however, their mechanism of activation has not been established. Here we elucidate a novel link between BRAF^V600E/ERK signaling and Abl kinases. We demonstrate that BRAF^V600E/ERK play a critical role in binding, phosphorylating and regulating Abl localization and Abl/Arg activation …

A Linkage Map For The Newt Notophthalmus Viridescens: Insights In Vertebrate Genome And Chromosome Evolution, Melissa C. Keinath, S. Randal Voss, Panagiotis A. Tsonis, Jeramiah J. Smith

Biology Faculty Publications

Genetic linkage maps are fundamental resources that enable diverse genetic and genomic approaches, including quantitative trait locus (QTL) analyses and comparative studies of genome evolution. It is straightforward to build linkage maps for species that are amenable to laboratory culture and genetic crossing designs, and that have relatively small genomes and few chromosomes. It is more difficult to generate linkage maps for species that do not meet these criteria. Here, we introduce a method to rapidly build linkage maps for salamanders, which are known for their enormous genome sizes. As proof of principle, we developed a linkage map with thousands …

Inducible Nitric Oxide Synthase (Inos) Is A Novel Negative Regulator Of Hematopoietic Stem/Progenitor Cell Trafficking, Mateusz Adamiak, Ahmed Abdelbaset-Ismail, Joseph B. Moore Iv, J. Zhao, Ahmed Abdel-Latif, Marcin Wysoczynski, Mariusz Z. Ratajczak

Internal Medicine Faculty Publications

Nitric oxide (NO) is a gaseous free radical molecule involved in several biological processes related to inflammation, tissue damage, and infections. Based on reports that NO inhibits migration of granulocytes and monocytes, we became interested in the role of inducible NO synthetase (iNOS) in pharmacological mobilization of hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM) into peripheral blood (PB). To address the role of NO in HSPC trafficking, we upregulated or downregulated iNOS expression in hematopoietic cell lines. Next, we performed mobilization studies in iNOS^−/− mice and evaluated engraftment of iNOS^−/− HSPCs in wild type (control) animals. Our …

Origins Of Thalamic And Cortical Projections To The Posterior Auditory Field In Congenitally Deaf Cats., Blake E Butler, Nicole Chabot, Andrej Kral, Stephen G Lomber

Psychology Publications

Crossmodal plasticity takes place following sensory loss, such that areas that normally process the missing modality are reorganized to provide compensatory function in the remaining sensory systems. For example, congenitally deaf cats outperform normal hearing animals on localization of visual stimuli presented in the periphery, and this advantage has been shown to be mediated by the posterior auditory field (PAF). In order to determine the nature of the anatomical differences that underlie this phenomenon, we injected a retrograde tracer into PAF of congenitally deaf animals and quantified the thalamic and cortical projections to this field. The pattern of projections from …

Progesterone Receptor And Prostaglandins Mediate Luteinizing Hormone-Induced Changes In Messenger Rnas For Adamts Proteases In Theca Cells Of Bovine Periovulatory Follicles, Erin L. Willis, Phillip J. Bridges, Joanne E. Fortune

Animal and Food Sciences Faculty Publications

Little is known about the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of extracellular proteases in ovarian follicles of non‐rodent species, particularly in theca cells. In the present study, temporal changes in the abundance of mRNA encoding four ADAMTS subtypes and hormonal regulation of mRNA encoding two subtypes were investigated in theca interna cells during the periovulatory period in cattle. Gonadotropin‐releasing hormone (GnRH) was injected into animals to induce a luteinizing hormone (LH)/follicle‐stimulating hormone (FSH) surge, and follicles were obtained at 0 hr post‐GnRH (preovulatory) or at 6, 12, 18, or 24 hr (periovulatory). ADAMTS1, ‐2, …

The Heat Shock Transcription Factor Hsf1 Induces Ovarian Cancer Epithelial-Mesenchymal Transition In A 3d Spheroid Growth Model., Chase D Powell, Trillitye R Paullin, Candice Aoisa, Christopher J Menzie, Ashley Ubaldini, Sandy D. Westerheid

Molecular Biosciences Faculty Publications

Ovarian cancer is the most lethal gynecological cancer, with over 200,000 women diagnosed each year and over half of those cases leading to death. The proteotoxic stress-responsive transcription factor HSF1 is frequently overexpressed in a variety of cancers and is vital to cellular proliferation and invasion in some cancers. Upon analysis of various patient data sets, we find that HSF1 is frequently overexpressed in ovarian tumor samples. In order to determine the role of HSF1 in ovarian cancer, inducible HSF1 knockdown cell lines were created. Knockdown of HSF1 in SKOV3 and HEY ovarian cancer cell lines attenuates the epithelial-to-mesenchymal transition …

Elevated Integrin Α6Β4 Expression Is Associated With Venous Invasion And Decreased Overall Survival In Non-Small Cell Lung Cancer, Rachel L. Stewart, Dava West, Chi Wang, Heidi L. Weiss, Tamas S. Gal, Eric B. Durbin, William O'Connor, Min Chen, Kathleen L. O'Connor

Pathology and Laboratory Medicine Faculty Publications

Lung cancer carries a poor prognosis and is the most common cause of cancer-related death worldwide. The integrin α6β4, a laminin receptor, promotes carcinoma progression in part by cooperating with various growth factor receptors to facilitate invasion and metastasis. In carcinoma cells with mutant TP53, the integrin α6β4 promotes cell survival. TP53 mutations and integrin α6β4 overexpression co-occur in many aggressive malignancies. Because of the high frequency of TP53 mutations in lung squamous cell carcinoma (SCC), we sought to investigate the association of integrin β4 expression with clinicopathologic features and survival in non–small cell lung cancer (NSCLC). We constructed …

Twist-Mediated Epithelial-Mesenchymal Transition Promotes Breast Tumor Cell Invasion Via Inhibition Of Hippo Pathway, Yifan Wang, Jingyi Liu, Xuhua Ying, Pengnian Charles Lin, Binhua P. Zhou

Molecular and Cellular Biochemistry Faculty Publications

Twist is a key transcription factor for Epithelial-mesenchymal transition (EMT), which is a cellular de-differentiation program that promotes invasion and metastasis, confers tumor cells with cancer stem cell (CSC)-like characteristics, and increases therapeutic resistance. However, the mechanisms that facilitate the functions of Twist remain unclear. Here we report that Twist overexpression increased expression of PAR1, an upstream regulator of the Hippo pathway; PAR1 promotes invasion, migration, and CSC-like properties in breast cancer by activating the transcriptional co-activator TAZ. Our study indicates that Hippo pathway inhibition is required for the increased migratory and invasiveness ability of breast cancer cells in Twist-mediated …

Estrogen Receptor Alpha (Esr1)-Dependent Regulation Of The Mouse Oviductal Transcriptome, Katheryn L. Cerny, Rosanne A. C. Ribeiro, Myoungkun Jeoung, Chemyong Ko, Phillip J. Bridges

Animal and Food Sciences Faculty Publications

Estrogen receptor-α (ESR1) is an important transcriptional regulator in the mammalian oviduct, however ESR1-dependent regulation of the transcriptome of this organ is not well defined, especially at the genomic level. The objective of this study was therefore to investigate estradiol- and ESR1-dependent regulation of the transcriptome of the oviduct using transgenic mice, both with (ESR1KO) and without (wild-type, WT) a global deletion of ESR1. Oviducts were collected from ESR1KO and WT littermates at 23 days of age, or ESR1KO and WT mice were treated with 5 IU PMSG to stimulate follicular development and the production of ovarian estradiol, and the …

Effect Of Hydroxychloroquine And Characterization Of Autophagy In A Mouse Model Of Endometriosis, A. Ruiz, S. Rockfield, N. Taran, E. Haller, Robert Engelman, I Flores, P Panina-Bordignon, Meera Nanjundan

Molecular Biosciences Faculty Publications

In endometriosis, the increased survival potential of shed endometrial cells (which normally undergo anoikis) is suggested to promote lesion development. One mechanism that may alter anoikis is autophagy. Using an autophagic flux inhibitor hydroxychloroquine (HCQ), we identified that it reduces the in vitro survival capacity of human endometriotic and endometrial T-HESC cells. We also identified that HCQ could decrease lesion numbers and disrupt lesion histopathology, as well as increase the levels of peritoneal macrophages and the IP-10 (10 kDa interferon-γ-induced protein) chemokine in a mouse model of endometriosis. We noted that RNA levels of a subset of autophagic …

Local Corticotropin Releasing Hormone (Crh) Signals To Its Receptor Crhr1 During Postnatal Development Of The Mouse Olfactory Bulb, Isabella Garcia, Paramjit K Bhullar, Burak Tepe, Joshua Ortiz-Guzman, Longwen Huang, Alexander M Herman, Lesley Chaboub, Benjamin Deneen, Nicholas J Justice, Benjamin R Arenkiel

Faculty, Staff and Students Publications

Neuropeptides play important physiological functions during distinct behaviors such as arousal, learning, memory, and reproduction. However, the role of local, extrahypothalamic neuropeptide signaling in shaping synapse formation and neuronal plasticity in the brain is not well understood. Here, we characterize the spatiotemporal expression profile of the neuropeptide corticotropin-releasing hormone (CRH) and its receptor CRHR1 in the mouse OB throughout development. We found that CRH-expressing interneurons are present in the external plexiform layer, that its cognate receptor is expressed by granule cells, and show that both CRH and CRHR1 expression enriches in the postnatal period when olfaction becomes important towards olfactory-related …

Age-Associated Methylation Suppresses Spry1, Leading To A Failure Of Re-Quiescence And Loss Of The Reserve Stem Cell Pool In Elderly Muscle., Anne Bigot, William J Duddy, Zamalou G Ouandaogo, Elisa Negroni, Virginie Mariot, Svetlana Ghimbovschi, Brennan Harmon, Aurore Wielgosik, Camille Loiseau, Joseph Devaney, Julie Dumonceaux, Gillian Butler-Browne, Vincent Mouly, Stéphanie Duguez

Genomics and Precision Medicine Faculty Publications

The molecular mechanisms by which aging affects stem cell number and function are poorly understood. Murine data have implicated cellular senescence in the loss of muscle stem cells with aging. Here, using human cells and by carrying out experiments within a strictly pre-senescent division count, we demonstrate an impaired capacity for stem cell self-renewal in elderly muscle. We link aging to an increased methylation of the SPRY1 gene, a known regulator of muscle stem cell quiescence. Replenishment of the reserve cell pool was modulated experimentally by demethylation or siRNA knockdown of SPRY1. We propose that suppression of SPRY1 by age-associated …

Pharmaceutical Integrated Stress Response Enhancement Protects Oligodendrocytes And Provides A Potential Multiple Sclerosis Therapeutic., Sharon W Way, Joseph R Podojil, Benjamin L Clayton, Anita Zaremba, Tassie L Collins, Rejani B Kunjamma, Andrew P Robinson, Pedro Brugarolas, Robert H. Miller, Stephen D Miller, Brian Popko

Anatomy and Regenerative Biology Faculty Publications

Oligodendrocyte death contributes to the pathogenesis of the inflammatory demyelinating disease multiple sclerosis (MS). Nevertheless, current MS therapies are mainly immunomodulatory and have demonstrated limited ability to inhibit MS progression. Protection of oligodendrocytes is therefore a desirable strategy for alleviating disease. Here we demonstrate that enhancement of the integrated stress response using the FDA-approved drug guanabenz increases oligodendrocyte survival in culture and prevents hypomyelination in cerebellar explants in the presence of interferon-γ, a pro-inflammatory cytokine implicated in MS pathogenesis. In vivo, guanabenz treatment protects against oligodendrocyte loss caused by CNS-specific expression of interferon-γ. In a mouse model of MS, experimental …

Cytometric Characterization Of Circulating Tumor Cells Captured By Microfiltration And Their Correlation To The Cellsearch(®) Ctc Test., Daniel L Adams, Steingrimur Stefansson, Christian Haudenschild, Stuart S Martin, Monica Charpentier, Saranya Chumsri, Massimo Cristofanilli, Cha-Mei Tang, R Katherine Alpaugh

Pathology Faculty Publications

Recent studies reporting hundreds, to thousands, of circulating tumor cells (CTCs) in the blood of cancer patients have raised questions regarding the prevalence of CTCs, as enumerated by the CellSearch(®) CTC Test. Although CellSearch has been shown to consistently detect clinically relevant CTCs; the ability to only capture EpCAM positive cells has led to speculation that it captures limited subsets of CTCs. In contrast, alternative approaches to CTC isolation are often cited as capturing large numbers of CTCs from patient blood. Not surprisingly the number of cells isolated by alternative approaches show poor correlations when compared to CellSearch, even when …

Clinical Significance Of A Point Mutation In Dna Polymerase Beta (Polb) Gene In Gastric Cancer., Xiaohui Tan, Hongyi Wang, Guangbin Luo, Shuyang Ren, Wenmei Li, Jiantao Cui, Harindarpal S. Gill, Sidney W. Fu, Youyong Lu

Medicine Faculty Publications

Gastric cancer (GC) is a major cause of global cancer mortality. Genetic variations in DNA repair genes can modulate DNA repair capability and, consequently, have been associated with risk of developing cancer. We have previously identified a T to C point mutation at nucleotide 889 (T889C) in DNA polymerase beta (POLB) gene, a key enzyme involved in base excision repair in primary GCs. The purpose of this study was to evaluate the mutation and expression of POLB in a larger cohort and to identify possible prognostic roles of the POLB alterations in GC. Primary GC specimens and their matched normal …

Large-Scale Identification Of Chemically Induced Mutations In Drosophila Melanogaster, Nele A Haelterman, Lichun Jiang, Yumei Li, Vafa Bayat, Hector Sandoval, Berrak Ugur, Kai Li Tan, Ke Zhang, Danqing Bei, Bo Xiong, Wu-Lin Charng, Theodore Busby, Adeel Jawaid, Gabriela David, Manish Jaiswal, Koen J T Venken, Shinya Yamamoto, Rui Chen, Hugo J Bellen

Faculty, Staff and Students Publications

Forward genetic screens using chemical mutagens have been successful in defining the function of thousands of genes in eukaryotic model organisms. The main drawback of this strategy is the time-consuming identification of the molecular lesions causative of the phenotypes of interest. With whole-genome sequencing (WGS), it is now possible to sequence hundreds of strains, but determining which mutations are causative among thousands of polymorphisms remains challenging. We have sequenced 394 mutant strains, generated in a chemical mutagenesis screen, for essential genes on the Drosophila X chromosome and describe strategies to reduce the number of candidate mutations from an average of …

The Development Of A Comprehensive Antifungal Susceptibility Testing Assay For Vulvovaginal Candidiasis Therapy, David Hardaker

Graduate School of Biomedical Sciences Theses and Dissertations

Vulvovaginal candidiasis is the most common fungal infection of the female urogenital tract, commonly caused by Candida albicans and C. glabrata. However, treatment can be difficult when caused by non-albicans strains due to resistance to the oral antifungal drug fluconazole. The mechanism through which strains of Candida, particularly C. glabrata, develop resistance to different antifungal classes has not been completely characterized. The ergosterol biosynthesis pathway, an important component of the cell membrane, is the major target of antifungals such as fluconazole, an inhibitor of the ERG 11 gene. Current research shows that an upregulation of specific genes in C. glabrata …

Trip/Nopo E3 Ubiquitin Ligase Promotes Ubiquitylation Of Dna Polymerase Η, Heather A. Wallace, Julie A. Merkle, Michael C. Yu, Taloa G. Berg, Ethan Lee, Giovanni Bosco, Laura A. Lee

Dartmouth Scholarship

We previously identified a Drosophila maternal effect-lethal mutant named ‘no poles’ (nopo). Embryos from nopo females undergo mitotic arrest with barrel-shaped, acentrosomal spindles during the rapid cycles of syncytial embryogenesis because of activation of a Chk2-mediated DNA checkpoint. NOPO is the Drosophila homolog of human TNF receptor associated factor (TRAF)-interacting protein (TRIP), which has been implicated in TNF signaling. NOPO and TRIP contain RING domains closely resembling those of known E3 ubiquitin ligases. We herein sought to elucidate the mechanism by which TRIP/NOPO promotes genomic stability by performing a yeast two-hybrid screen to identify potential substrates/interactors. We identified members of …

Myo/Nog Cells: Targets For Preventing The Accumulation Of Skeletal Muscle-Like Cells In The Human Lens, Jacquelyn Gerhart, M. Greenbaum, V. Scheinfeld, P. Fitzgerald, M. Crawford, Arturo Bravo Nuevo, M. Pitts, Mindy George-Weinstein

PCOM Scholarly Works

Posterior capsule opacification (PCO) is a vision impairing condition that arises in some patients following cataract surgery. The fibrotic form of PCO is caused by myofibroblasts that may emerge in the lens years after surgery. In the chick embryo lens, myofibroblasts are derived from Myo/Nog cells that are identified by their expression of the skeletal muscle specific transcription factor MyoD, the bone morphogenetic protein inhibitor Noggin, and the epitope recognized by the G8 monoclonal antibody. The goal of this study was to test the hypothesis that depletion of Myo/Nog cells will prevent the accumulation of myofibroblasts in human lens tissue. …

Adam17-Mediated Processing Of Tnf-Α Expressed By Antiviral Effector Cd8+ T Cells Is Required For Severe T-Cell-Mediated Lung Injury, Matthew P. Deberge, Kenneth H. Ely, Guang-Shing Cheng, Richard I. Enelow

Dartmouth Scholarship

Influenza infection in humans evokes a potent CD8+ T-cell response, which is important for clearance of the virus but may also exacerbate pulmonary pathology. We have previously shown in mice that CD8+ T-cell expression of TNF-a is required for severe and lethal lung injury following recognition of an influenza antigen expressed by alveolar epithelial cells. Since TNF-a is first expressed as a transmembrane protein that is then proteolytically processed to release a soluble form, we sought to characterize the role of TNF-a processing in CD8+ T-cell-mediated injury. In this study we observed that inhibition of ADAM17-mediated processing of TNF-a by …

Pv1 Down-Regulation Via Shrna Inhibits The Growth Of Pancreatic Adenocarcinoma Xenografts, Sophie J. Deharvengt, Dan Tse, Olga Sideleva, Caitlin Mcgarry, Jason R. Gunn, Daniel S. Longnecker, Catherine Carriere, Radu V. Stan

Dartmouth Scholarship

PV1 is an endothelial-specific protein with structural roles in the formation of diaphragms in endothelial cells of normal vessels. PV1 is also highly expressed on endothelial cells of many solid tumours. On the basis of in vitro data, PV1 is thought to actively participate in angiogenesis. To test whether or not PV1 has a function in tumour angiogenesis and in tumour growth in vivo, we have treated pancreatic tumour-bearing mice by single-dose intratumoural delivery of lentiviruses encoding for two different shRNAs targeting murine PV1. We find that PV1 down-regulation by shRNAs inhibits the growth of established tumours derived from two …

Effects Of Aging On Regulators Of Muscle Apoptosis In The Female F344bn Rat, Murali K. Gadde

Theses, Dissertations and Capstones

Age-related muscle atrophy is a consequence of normal aging characterized by decreases in muscle mass and strength. The mechanism(s) underlying the loss of muscle mass with increasing age is not fully understood, however recent data has suggested that muscle cell apoptosis may be involved. Here we investigate how aging affects the regulation of muscle apoptosis in the extensor digitorum longus (EDL) and soleus muscles of young (6-month), aged (26-month), and very aged (30-month) female Fischer 344/NNiaHSD X Brown Norway / BiNia (F344BN) rats. EDL and soleus muscle mass/body weight ratios were lower in aged animals but not different between 26- …

Adenomatous Polyposis Coli Is Present Near The Minimal Level Required For Accurate Graded Responses To The Wingless Morphogen, Hassina Benchabane, Edward G. Hughes, Carter M. Takacs, Jason R. Baird, Yashi Ahmed

Dartmouth Scholarship

The mechanisms by which the Wingless (Wg) morphogen modulates the activity of the transcriptional activator Armadillo (Arm) to elicit precise, concentration-dependent cellular responses remain uncertain. Arm is targeted for proteolysis by the Axin/Adenomatous polyposis coli (Apc1 and Apc2)/Zeste-white 3 destruction complex, and Wg-dependent inactivation of destruction complex activity is crucial to trigger Arm signaling. In the prevailing model for Wg transduction, only Axin levels limit destruction complex activity, whereas Apc is present in vast excess. To test this model, we reduced Apc activity to different degrees, and analyzed the effects on three concentration-dependent responses to Arm signaling that specify distinct …

Aging Predisposes Oocytes To Meiotic Nondisjunction When The Cohesin Subunit Smc1 Is Reduced, Vijayalakshmi V. Subramanian, Sharon E. Bickel

Dartmouth Scholarship

In humans, meiotic chromosome segregation errors increase dramatically as women age, but the molecular defects responsible are largely unknown. Cohesion along the arms of meiotic sister chromatids provides an evolutionarily conserved mechanism to keep recombinant chromosomes associated until anaphase I. One attractive hypothesis to explain age- dependent nondisjunction (NDJ) is that loss of cohesion over time causes recombinant homologues to dissociate prematurely and segregate randomly during the first meiotic division. Using Drosophila as a model system, we have tested this hypothesis and observe a significant increase in meiosis I NDJ in experimentally aged Drosophila oocytes when the cohesin protein SMC1 …

Regulation Of Meiotic Cohesion And Chromosome Core Morphogenesis During Pachytene In Drosophila Oocytes, Radhika S. Khetani, Sharon E. Bickel

Dartmouth Scholarship

During meiosis, cohesion between sister chromatids is required for normal levels of homologous recombination, maintenance of chiasmata and accurate chromosome segregation during both divisions. In Drosophila, null mutations in the ord gene abolish meiotic cohesion, although how ORD protein promotes cohesion has remained elusive. We show that SMC subunits of the cohesin complex colocalize with ORD at centromeres of ovarian germ-line cells. In addition, cohesin SMCs and ORD are visible along the length of meiotic chromosomes during pachytene and remain associated with chromosome cores following DNase I digestion. In flies lacking ORD activity, cohesin SMCs fail to accumulate at oocyte …