Medicine and Health Sciences Commons^™

Causal Effects On Complex Traits Are Similar For Common Variants Across Segments Of Different Continental Ancestries Within Admixed Individuals, Kangcheng Hou, Yi Ding, Ziqi Xu, Yue Wu, Arjun Bhattacharya, Rachel Mester, Gillian M Belbin, Steve Buyske, David V Conti, Burcu F Darst, Myriam Fornage, Chris Gignoux, Xiuqing Guo, Christopher Haiman, Eimear E Kenny, Michelle Kim, Charles Kooperberg, Leslie Lange, Ani Manichaikul, Kari E North, Ulrike Peters, Laura J Rasmussen-Torvik, Stephen S Rich, Jerome I Rotter, Heather E Wheeler, Genevieve L Wojcik, Ying Zhou, Sriram Sankararaman, Bogdan Pasaniuc

Student and Faculty Publications

Individuals of admixed ancestries (for example, African Americans) inherit a mosaic of ancestry segments (local ancestry) originating from multiple continental ancestral populations. This offers the unique opportunity of investigating the similarity of genetic effects on traits across ancestries within the same population. Here we introduce an approach to estimate correlation of causal genetic effects (radmix) across local ancestries and analyze 38 complex traits in African-European admixed individuals (N = 53,001) to observe very high correlations (meta-analysis radmix = 0.95, 95% credible interval 0.93-0.97), much higher than correlation of causal effects across continental ancestries. We replicate our results using regression-based methods …

Knowledge And Practice Regarding Prostate Cancer Germline Testing Among Urologists: Gaps To Address For Optimal Implementation, Stacy Loeb, Nataliya Byrne, Dawn Walter, Danil V Makarov, David R Wise, Daniel Becker, Veda N Giri

Department of Medical Oncology Faculty Papers

BACKGROUND: Germline testing is recommended for all men with metastatic prostate cancer (PCa), and for some with localized PCa meeting specific histologic or family history criteria. Germline genetic evaluation has important implications for PCa prognosis and management, as well as implications for family members and cancer screening. Despite the importance of germline evaluation, its utilization in urologic practice is unknown.

MATERIALS AND METHODS: We conducted a 32-item survey of U.S. urologists to examine knowledge of germline testing guidelines and practice patterns. It was shared through email to 6 American Urological Association sections, the Veterans Affairs Urology Mailgroup, and social media. …

Sensors And Wearables In Oncology: A Study Of The Barriers And Facilitators To Adoption, Sam Hanna

Doctor of Philosophy in Translational Health Sciences Dissertations

Innovation, although a subject of considerable debate (e.g., Baregheh et al., 2009; Christensen, 1997), can be defined as the introduction and dissemination of a new or a different idea into use or practice that drives impact (Solis and Sinfield, 2014). Many studies and editorials have highlighted the complexity of the United States health system and detailed the slow speed by which innovative ideas materialize into impactful innovations (Continuing America’s leadership (2017); England & Stewart (2007); Kannampallil, Schauer, Cohen & Patel (2011)). While there are many advances in sensor and wearable technologies in this instance, the adoption rate by oncologists has …

Genetic Relationships And Therapeutic Options For Relapsed Acute Lymphoblastic Leukemia, Hailie Shertzer

Senior Honors Theses

Acute lymphoblastic leukemia (ALL) is the most common form of cancer among children and can be lethal to the adult population. Though 80% of patients with ALL reach complete remission after treatment, about 20% of those diagnosed fail to remain cancer-free. Genetic rearrangements are the hallmark of relapsed ALL, but the mechanism by which these rearrangements occur is still unclear. Recent research suggests these mutations may be detectable during initial diagnosis. If researchers are able to accurately assess the probability of relapse during diagnosis by analyzing the genome of the leukemic cells, the likelihood of administering effective therapy would increase. …

A Look At Gene Control: Tracking The Ccnd1 Gene, Bryan Anders

Mahurin Honors College Capstone Experience/Thesis Projects

Cancer occurs when the cell does not properly control its own cell cycle. It then replicates in an out of control fashion leading to the death of various organs and then the demise of the organism as a whole. As it seems to have always been a problem for cell-based life, certain safeguards against cancer have been evolved over time. One such method comes in the form of prevention via cyclin proteins, which are encoded from cyclin genes. The gene that is the focus of this research is the CCND1, or cyclin D1, gene that controls the progression through various …

Prognostication Of Uveal Melanoma Is Simple And Highly Predictive Using The Cancer Genome Atlas (Tcga) Classification: A Review., Carol L. Shields, Lauren A. Dalvin, Pornpattana Vichitvejpaisal, Mehdi Mazloumi, Arupa Ganguly, Jerry A. Shields

Wills Eye Hospital Papers

Purpose: The cancer genome atlas (TCGA) is a comprehensive project supported by the National Cancer Institute (NCI) in the United States to explore molecular alterations in cancer, including uveal melanoma (UM). This led to TCGA classification for UM. In this report, we review the American Joint Committee on Cancer (AJCC) classification and TCGA classification for UM from the NCI's Center for Cancer Genomics (NCI CCG) (based on enucleation specimens [n = 80 eyes]) and from Wills Eye Hospital (WEH) (based on fine needle aspiration biopsy [FNAB] specimens [n = 658 eyes]). We then compare accuracy and predictability of AJCC versus …

Differential Iron Regulatory Genetics In 2d & 3d Culture Of Breast Cancer Cells, Tyler Hanna, Suzy Torti Ph. D, Frank Torti M.D., Mph, Nicole Farra Ph. D.

Honors Scholar Theses

The iron regulatory axis has consistently been shown to be perturbed in cancer cell lines relative to non-cancerous cell lines. As cancer cells rapidly divide and grow, they require iron to fuel many intracellular processes, including DNA replication and protein synthesis. Three-dimensional cell culture is an increasingly popular method of culture that purportedly more accurately mimics the in vivo microenvironment of cancers over traditional two-dimensional culture. This project was prompted by previous lab results to investigate differential iron regulatory gene expression in 2D and 3D spheroid culture models. We replicated the findings that the gene hepcidin is induced in 3D …

Epidemiology Of Moderate Alcohol Consumption And Breast Cancer: Association Or Causation?, Samir Zakhari, Jan B. Hoek

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Epidemiological studies have been used to show associations between modifiable lifestyle habits and the incidence of breast cancer. Among such factors, a history of alcohol use has been reported in multiple studies and meta-analyses over the past decades. However, associative epidemiological studies that were interpreted as evidence that even moderate alcohol consumption increases breast cancer incidence have been controversial. In this review, we consider the literature on the relationship between moderate or heavy alcohol use, both in possible biological mechanisms and in variations in susceptibility due to genetic or epigenetic factors. We argue that there is a need to incorporate …

Cyclin-Dependent Kinase Inhibitor P1446a Induces Apoptosis In A Jnk/P38 Mapk-Dependent Manner In Chronic Lymphocytic Leukemia B-Cells, Cody Paiva, J. Claire Godbersen, Ryan S. Soderquist, Taylor Rowland, Sumner Kilmarx

Dartmouth Scholarship

CDK (cyclin-dependent kinase) inhibitors have shown remarkable activity in CLL, where its efficacy has been linked to inhibition of the transcriptional CDKs (7 and 9) and deregulation of RNA polymerase and short-lived pro-survival proteins such as MCL1. Furthermore, ER (endoplasmic reticulum) stress has been implicated in CDK inhibition in CLL. Here we conducted a pre-clinical study of a novel orally active kinase inhibitor P1446A in CLL B-cells. P1446A inhibited CDKs at nanomolar concentrations and induced rapid apoptosis of CLL cells in vitro, irrespective of chromosomal abnormalities or IGHV mutational status. Apoptosis preceded inactivation of RNA polymerase, and was accompanied by …

Role Of A Genetic Variant On The 15q25.1 Lung Cancer Susceptibility Locus In Smoking-Associated Nasopharyngeal Carcinoma, Xuemei Ji, Weidong Zhang, Jiang Gui, Xia Fan, Weiwei Zhang, Yafang Li, Guangyu An, Dakai Zhu, Qiang Hu

Dartmouth Scholarship

Background: The 15q25.1 lung cancer susceptibility locus, containing CHRNA5, could modify lung cancer susceptibility and multiple smoking related phenotypes. However, no studies have investigated the association between CHRNA5 rs3841324, which has been proven to have the highest association with CHRNA5 mRNA expression, and the risk of other smoking-associated cancers, except lung cancer. In the current study we examined the association between rs3841324 and susceptibility to smoking-associated nasopharyngeal carcinoma (NPC).

Methods: In this case-control study we genotyped the CHRNA5 rs3841324 polymorphism with 400 NPC cases and 491 healthy controls who were Han Chinese and frequency-matched by age (±5 years), gender, and …

Influence Networks Based On Coexpression Improve Drug Target Discovery For The Development Of Novel Cancer Therapeutics, Nadia M. Penrod, Jason H. Moore

Dartmouth Scholarship

Background: Thedemandfornovelmolecularlytargeteddrugswillcontinuetoriseaswemoveforwardtowardthe goal of personalizing cancer treatment to the molecular signature of individual tumors. However, the identification of targets and combinations of targets that can be safely and effectively modulated is one of the greatest challenges facing the drug discovery process. A promising approach is to use biological networks to prioritize targets based on their relative positions to one another, a property that affects their ability to maintain network integrity and propagate information-flow. Here, we introduce influence networks and demonstrate how they can be used to generate influence scores as a network-based metric to rank genes as potential drug targets. …

Wnt Pathway Reprogramming During Human Embryonal Carcinoma Differentiation And Potential For Therapeutic Targeting, Grace E. Snow, Allison C. Kasper, Alexander M. Busch, Elisabeth Schwarz, Katherine E. Ewings, Thomas Bee, Michael J. Spinella, Ethan Dmitrovsky, Sarah J. Freemantle

Dartmouth Scholarship

Testicular germ cell tumors (TGCTs) are classified as seminonas or non-seminomas of which a major subset is embryonal carcinoma (EC) that can differentiate into diverse tissues. The pluripotent nature of human ECs resembles that of embryonic stem (ES) cells. Many Wnt signalling species are regulated during differentiation of TGCT-derived EC cells. This study comprehensively investigated expression profiles of Wnt signalling components regulated during induced differentiation of EC cells and explored the role of key components in maintaining pluripotency.

Let-7 Expression Defines Two Differentiation Stages Of Cancer, Scott Shell, Sun-Mi Park, Amir Reza Radjabi, Robert Schickel, Emily Kistner, David Jewell

Dartmouth Scholarship

The early phases of carcinogenesis resemble embryonic development, often involving the reexpression of embryonic mesenchymal genes. The NCI60 panel of human tumor cell lines can genetically be subdivided into two superclusters (SCs) that correspond to CD95 Type I and II cells. SC1 cells are characterized by a mesenchymal and SC2 cells by an epithelial gene signature, suggesting that SC1 cells represent less differentiated, advanced stages of cancer. miRNAs are small 20- to 22-nucleotide-long noncoding RNAs that inhibit gene expression at the posttranscriptional level. By performing miRNA expression analysis on 10 Type I and 10 Type II cells, we have determined …

Association Of The Tensin N-Terminal Protein-Tyrosine Phosphatase Domain With The Alpha Isoform Of Protein Phosphatase-1 In Focal Adhesions, Masumi Eto, Jason Kirkbride, Elizabeth Elliott, Su Hao Lo, David L. Brautigan

Department of Molecular Physiology and Biophysics Faculty Papers

Focal adhesions attach cultured cells to the extracellular matrix, and we found endogenous protein phosphatase-1alpha isoform (PP1alpha) localized in adhesions across the entire area of adherent fibroblasts. However, in fibroblasts migrating into a scrape wound or spreading after replating PP1alpha did not appear in adhesions near the leading edge but was recruited into other adhesions coincident in time and space with incorporation of tensin. Endogenous tensin and PP1alpha co-precipitated from cell lysates with isoform-specific PP1 antibodies. Chemical cross-linking of focal adhesion preparations with Lomant's reagent demonstrated molecular proximity of endogenous PP1alpha and tensin, whereas neither focal adhesion kinase nor vinculin …

Estimation Of The Incidence Of A Rare Genetic Disease Through A Two-Tier Mutation Survey, R Chakraborty, M R Srinivasan, S Raskin

Student and Faculty Publications

Recent attempts to detect mutations involving single base changes or small deletions that are specific to genetic diseases provide an opportunity to develop a two-tier mutation-screening program through which incidence of rare genetic disorders and gene carriers may be precisely estimated. A two-tier survey consists of mutation screening in a sample of patients with specific genetic disorders and in a second sample of newborns from the same population in which mutation frequency is evaluated. We provide the statistical basis for evaluating the incidence of affected and gene carriers in such two-tier mutation-screening surveys, from which the precision of the estimates …

Statistical Interpretation Of Dna Typing Data, R Chakraborty

Student and Faculty Publications

No abstract provided.

Population Amalgamation And Genetic Variation: Observations On Artificially Agglomerated Tribal Populations Of Central And South America, R Chakraborty, P E Smouse, J V Neel

Student and Faculty Publications

The interpretation of data on genetic variation with regard to the relative roles of different evolutionary factors that produce and maintain genetic variation depends critically on our assumptions concerning effective population size and the level of migration between neighboring populations. In humans, recent population growth and movements of specific ethnic groups across wide geographic areas mean that any theory based on assumptions of constant population size and absence of substructure is generally untenable. We examine the effects of population subdivision on the pattern of protein genetic variation in a total sample drawn from an artificial agglomerate of 12 tribal populations …