Medicine and Health Sciences Commons^™

Dna Methylation-Based Epigenetic Biomarkers In Cell-Type Deconvolution And Tumor Tissue Of Origin Identification, Ze Zhang

Dartmouth College Ph.D Dissertations

DNA methylation is an epigenetic modification that regulates gene expression and is essential to establishing and preserving cellular identity. Genome-wide DNA methylation arrays provide a standardized and cost-effective approach to measuring DNA methylation. When combined with a cell-type reference library, DNA methylation measures allow the assessment of underlying cell-type proportions in heterogeneous mixtures. This approach, known as DNA methylation deconvolution or methylation cytometry, offers a standardized and cost-effective method for evaluating cell-type proportions. While this approach has succeeded in discerning cell types in various human tissues like blood, brain, tumors, skin, breast, and buccal swabs, the existing methods have major …

A Review Of How Bioinformatics And Genome Sequencing Are Affecting Precision Medicine, Taylor S. Hickey

Honors Theses

Advancement in genomic sequencing and bioinformatics methods have been affecting biomedical research through precision medicine, especially in the area of cancer. Vaccine therapies can be developed using neoantigens that target specific mutations in tumors. The goals of this research are to identify mutations that lead to cancer and then define subpopulations in which patients can easily be identified. The future goal is to have targeted vaccines that are specific to each subpopulation ready to be used in treatment of their cancer. Limitations to reaching these goals have been due to tumor heterogeneity, cancer location, and difficulty in creating neoantigens for …

A Dna-Peptide Crosslink (Dpc) Increases Mutagenicity In Sos-Induced Escherichia Coli, Alessandra Bassani

Honors Scholar Theses

Bacteria, such as Escherichia coli, have an inducible system in response to DNA damage termed the SOS response. This system is activated when the replicative DNA polymerase (Pol) III encounters a lesion, uncouples from DNA helicase, and single-stranded DNA (ssDNA) accumulates at the replication fork. In this study, we investigated DNA-peptide crosslink (DpC), a common lesion that results from cross-linking of proteins or peptides, UV irradiation, and alkylating agents. To increase survival following formation of a lesion, the SOS response can utilize homologous recombination, translesion synthesis (TLS), or excision repair. With TLS, the levels of DNA Pol II, IV, …

Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty

Honors Theses and Capstones

Nearly one out of six deaths in 2020, around ten million people, were caused by cancer, making it a leading cause of death worldwide (WHO, 2022). This major public health issue, in addition to the rise of multidrug-resistant (MDR) pathogens, provides a high demand for the discovery of new pharmaceutical drugs to be used clinically to treat these conditions. The Streptomyces genus accounts to produce 39% of all microbial metabolites currently approved for human health, indicating its potential as an important species to study for antimicrobial and anticancer agents. The long linear genome of Streptomyces contains specialized sequences known as …

A Machine Learning Framework For Identifying Molecular Biomarkers From Transcriptomic Cancer Data, Md Abdullah Al Mamun

FIU Electronic Theses and Dissertations

Cancer is a complex molecular process due to abnormal changes in the genome, such as mutation and copy number variation, and epigenetic aberrations such as dysregulations of long non-coding RNA (lncRNA). These abnormal changes are reflected in transcriptome by turning oncogenes on and tumor suppressor genes off, which are considered cancer biomarkers.

However, transcriptomic data is high dimensional, and finding the best subset of genes (features) related to causing cancer is computationally challenging and expensive. Thus, developing a feature selection framework to discover molecular biomarkers for cancer is critical.

Traditional approaches for biomarker discovery calculate the fold change for each …

Targeting Plasma Membrane Phosphatidylserine Content To Inhibit Oncogenic Kras Function, Walaa E. Kattan

Dissertations & Theses (Open Access)

The small GTPase KRAS, which is frequently mutated in human cancers, must be localized to the plasma membrane (PM) for biological activity. We recently showed that the KRAS C-terminal membrane anchor exhibits exquisite lipid-binding specificity for select species of phosphatidylserine (PtdSer). We therefore investigated whether reducing PM PtdSer content is sufficient to abrogate KRAS oncogenesis. Oxysterol-related binding proteins ORP5 and ORP8 exchange PtdSer synthesized in the ER for phosphatidylinositol-4-phosphate (PI4P) synthesized in the PM. We show that depletion of ORP5 or ORP8 reduced PM PtdSer levels, resulting in extensive mislocalization of KRAS from the PM. Concordantly, ORP5 or ORP8 depletion …

Understanding The Pathogenesis Of Renal Medullary Carcinoma, Melinda Soeung

Dissertations & Theses (Open Access)

Renal medullary carcinoma (RMC) is a lethal cancer that predominantly affects young individuals with sickle cell trait (SCT). It is not currently understood why RMC only affects certain individuals with SCT. We found that patients with RMC more frequently participated in high-intensity exercise than matched controls. Using mouse models of SCT, we demonstrated the significant increase of renal hypoxia in the right kidney following high- but not moderate-intensity exercise. We also demonstrated in cell culture studies that SMARCB1 is ubiquitinated for proteasome-mediated degradation in hypoxia, and the re-expression of SMARCB1 leads to compromised proliferation in renal cells specifically in the …

Unveiling Global Roles Of G-Quadruplexes And G4-22 In Human Genetics, Ruth Barros De Paula

Dissertations & Theses (Open Access)

G-quadruplexes are non-B DNA structures formed by four or more runs of repeated guanines that confer unique features to living organism’s genomes. These sequences are enriched in regulatory regions, such as promoters and 5’ UTRs, and have distinct regulatory roles in both health and disease states. Even though previous studies showed the impact of G4 in gene expression, none of them summarized the location-specific effect of G4. Also, there is no broad understanding about the most common G4 repeat in the human genome, named here as G4-22, and how it links to the evolution of mammals and their biology. In …

An Investigation On The Irish Population’S Attitudes And Knowledge Towards Genetic Screening For Cancer, Emer Mccarthy, Ada Fleming, Dawn Hannah Cronin

International Undergraduate Journal of Health Sciences

Genetic mutations are alterations in DNA that may result in the development of a disease later in life. A BRCA gene is a tumour suppressor gene that helps to prevent the development of some cancers, particularly breast cancer. If a mutation occurs, this gene no longer functions at preventing these cancers. Genetic screening is when a population is tested for a mutation in an attempt to identify a group of people that are positive for the mutation. This can help identify cancer in different populations as well as track their inheritance. This study was conducted online, questioning the Irish populations …

Full Issue: The International Undergraduate Journal Of Health Sciences, Volume 1, Issue 1, June 2021

International Undergraduate Journal of Health Sciences

The full June 2021 issue (Volume 1, Issue 1) of the International Undergraduate Journal of Health Sciences

Assessing Genetic Counselors' Clinical Approach And Practices Regarding Pathogenic/Likely Pathogenic Variant Downgrades, Grant Bonesteele

Dissertations & Theses (Open Access)

Although rare, variant downgrades from a pathogenic/likely pathogenic (P/LP) variant to a variant of uncertain significance can have a significant impact on patients and their families in the clinical cancer setting. However, there is a lack of literature about how to approach these potentially challenging cases as a genetic counselor. Therefore, we aimed to characterize genetic counselors’ experiences, approach, and practices to variant downgrade cases using an online survey. The survey asked participants how they would approach variant downgrade scenarios involving the CDH1 or ATM genes with variable family histories. Genetic counselors appear to be united in whether they would …

Mixture Model Approaches To Integrative Analysis Of Multi-Omics Data And Spatially Correlated Genomic Data, Ziqiao Wang

Dissertations & Theses (Open Access)

Integrative genomic data analysis is a powerful tool to study the complex biological processes behind a disease. Statistical methods can model the interrelationships of the involved gene activities through jointly analyzing multiple types of genomic data from different platforms (vertical integration), or improve the power of a study through aggregating the same type of genomic data across studies (horizontal integration). In this dissertation, we propose statistical methods and strategies for integrative multi-omics data in association analysis of disease phenotypes, with an emphasis on cancer applications.

We develop a new strategy based on horizontal integration by leveraging publicly available datasets into …

Investigation Of Proliferation Suppressors In Genetic Fitness Screens, Walter Frank Lenoir Iv

Dissertations & Theses (Open Access)

Innovation of CRISPR gene-editing technology has provided scientists genome manipulation tools that allowed rapid advancement of scientific capabilities and thus improved our ability to systematically study mammalian genetic functional profiles. Genome-wide CRISPR knockout screens conducted in collections of human cell lines can knock out genes at multiple loci, and have provided new insights into functional roles for independent genes. This method has launched massive efforts in looking across genetic backgrounds for context specific genetic vulnerabilities within cancer. Much of the research effort thus far has been spent on optimizing phenotype distinctions between essential, genes required for cell fitness, and non-essential, …

Statistical Methods For Resolving Intratumor Heterogeneity With Single-Cell Dna Sequencing, Alexander Davis

Dissertations & Theses (Open Access)

Tumor cells have heterogeneous genotypes, which drives progression and treatment resistance. Such genetic intratumor heterogeneity plays a role in the process of clonal evolution that underlies tumor progression and treatment resistance. Single-cell DNA sequencing is a promising experimental method for studying intratumor heterogeneity, but brings unique statistical challenges in interpreting the resulting data. Researchers lack methods to determine whether sufficiently many cells have been sampled from a tumor. In addition, there are no proven computational methods for determining the ploidy of a cell, a necessary step in the determination of copy number. In this work, software for calculating probabilities from …

Assay Development For Isolation And Characterization Of Anticancer Properties Of Marine Fungi, Kyra Ricci

Honors Theses

Metabolites from fungi have potential use in the drug discovery process and have been used in the past to develop therapeutic agents for human use. Initial characterization of potential therapeutic properties of fungi is thus an important first step in identifying novel therapeutic compounds. In the present study, marine fungi were isolated from Myrtle Beach and assayed for anticancer properties using the soft agar colony formation assay in a 3D in vitro cellular environment. Many species were isolated from environmental samples, displaying unique morphologies and growth patterns. To optimize the soft agar assay in a six-well cell culture plate for …

10th Annual Postdoctoral Science Symposium, University Of Texas Md Anderson Cancer Center Postdoctoral Association

Annual Postdoctoral Science Symposium Abstracts

The Annual Postdoctoral Science Symposium (APSS) was initiated on August 4, 2011, by the MD Anderson Postdoctoral Association to provide a platform for talented postdoctoral fellows throughout the Texas Medical Center to present their work to a wider audience.

APSS is a scientific symposium organized by postdoctoral fellows from The University of Texas MD Anderson Cancer Center that welcomes submissions and presentations from postdoctoral fellows from all Texas Medical Center affiliated institutions and other Houston area institutions. The APSS provides a professional venue for postdoctoral scientists to develop, clarify and refine their research as result of formal reviews and critiques …

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 …

9th Annual Postdoctoral Science Symposium, University Of Texas Md Anderson Cancer Center Postdoctoral Association

Annual Postdoctoral Science Symposium Abstracts

The mission of the Annual Postdoctoral Science Symposium (APSS) is to provide a platform for talented postdoctoral fellows throughout the Texas Medical Center to present their work to a wider audience. The MD Anderson Postdoctoral Association convened its inaugural Annual Postdoctoral Science Symposium (APSS) on August 4, 2011.

The APSS provides a professional venue for postdoctoral scientists to develop, clarify, and refine their research as a result of formal reviews and critiques of faculty and other postdoctoral scientists. Additionally, attendees discuss current research on a broad range of subjects while promoting academic interactions and enrichment and developing new collaborations.

Investigating The Role Of Cd109 In Pancreatic Ductal Adenocarcinoma, Mennatallah Shaheen

Dissertations & Theses (Open Access)

Pancreatic Ductal Adenocarcinoma (PDAC) is the 3rd leading cause of cancer death in the US. We performed loss of function genomic screening on a cohort of four patient derived PDAC cell populations and our data shows a cell surface receptor CD109 to be a common vulnerability, the biologic role of which in PDAC is yet unstudied and largely unknown. We hypothesized that CD109 expression provides PDAC cells with a survival advantage, and promotes cancer progression through activation of downstream signaling. We believe therefore that targeting CD109 could improve PDAC patients’ survival. Here we report that CD109 plays a role in …

Identifying Pathogenic Variants In Hereditary Cancer Syndrome Genes Via Tumor Molecular Profiling, Carol Nowlen

Dissertations & Theses (Open Access)

Tumor molecular profiling is often performed in order to direct cancer treatment options. However, because many of the genes analyzed on tumor molecular profiling overlap with genes known to be associated in the germline with hereditary cancer predisposition syndromes, tumor molecular profiling can unknowingly uncover germline predisposition to cancer development. In this study, we determined the number of patients with pathogenic variants (PVs) identified in BRCA1 and BRCA2 (BRCA1/2) via tumor molecular profiling at The University of Texas MD Anderson Cancer Center, then performed a retrospective chart review to determine the proportion of such patients that received germline …

Shared Heritability And Functional Enrichment Across Six Solid Cancers, Xia Jiang, Hilary K. Finucane, Fredrick R. Schumacher, Stephanie L. Schmit, Jonathan P. Tyrer, Younghun Han, Kyriaki Michailidou, Corina Lesseur, Karoline B. Kuchenbaecker, Joe Dennis, David V. Conti, Graham Casey, Mia M. Gaudet, Jeroen R. Huyghe, Demetrius Albanes, Melinda C. Aldrich, Angeline S. Andrew, Irene L. Andrulis, Hoda Anton-Culver, Antonis C. Antoniou, Natalia N. Antonenkova, Susanne M. Arnold, Kristan J. Aronson, Banu K. Arun, Elisa V. Bandera, Rosa B. Barkardottir, Daniel R. Barnes, Jyotsna Batra, Matthias W. Beckmann, Javier Benitez

Markey Cancer Center Faculty Publications

Quantifying the genetic correlation between cancers can provide important insights into the mechanisms driving cancer etiology. Using genome-wide association study summary statistics across six cancer types based on a total of 296,215 cases and 301,319 controls of European ancestry, here we estimate the pair-wise genetic correlations between breast, colorectal, head/neck, lung, ovary and prostate cancer, and between cancers and 38 other diseases. We observed statistically significant genetic correlations between lung and head/neck cancer (r_g = 0.57, p = 4.6 × 10⁻⁸), breast and ovarian cancer (r_g = 0.24, p = 7 × 10^{−5 …}

Cyclin C: The Story Of A Non-Cycling Cyclin., Jan Ježek, Daniel G J Smethurst, David C Stieg, Z A C Kiss, Sara E Hanley, Vidyaramanan Ganesan, Kai-Ti Chang, Katrina F Cooper, Randy Strich

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

The class I cyclin family is a well-studied group of structurally conserved proteins that interact with their associated cyclin-dependent kinases (Cdks) to regulate different stages of cell cycle progression depending on their oscillating expression levels. However, the role of class II cyclins, which primarily act as transcription factors and whose expression remains constant throughout the cell cycle, is less well understood. As a classic example of a transcriptional cyclin, cyclin C forms a regulatory sub-complex with its partner kinase Cdk8 and two accessory subunits Med12 and Med13 called the Cdk8-dependent kinase module (CKM). The CKM reversibly associates with the multi-subunit …

An Inflammatory Landscape For Preoperative Neurologic Deficits In Glioblastoma., Amal Katrib, Hyun-Hwan Jeong, Nina L Fransen, Kristin S Henzel, Jeremy A Miller

Articles, Abstracts, and Reports

No abstract provided.

The Role Of Tumor Suppressor Dear1 In The Acquisition Of Mammary Stem/Progenitor Cell Properties, Uyen Le

Dissertations & Theses (Open Access)

Breast cancer is the most commonly diagnosed cancer in women in America. Ductal carcinoma in situ (DCIS), one of the earliest pre-invasive forms of invasive ductal carcinoma (IDC), has a 30-50% risk of progressing to IDC. Understanding the mechanisms regulating progression from DCIS to IDC would help identify biomarkers to stratify patients at higher risk of progression or metastasis. Cumulative literature suggests the earliest phase of dissemination from the primary tumor is driven by the epithelial-mesenchymal transition (EMT) program. DEAR1 is a tumor suppressor gene which is mutated, undergoes loss of heterozygosity in breast cancer, and is downregulated in DCIS …

Computational Insights Into The Generation Of Chromosomal Copy Number Changes, Yihua Liu

Dissertations & Theses (Open Access)

Deviations from a diploid configuration of the human genome, spanning single genes or entire chromosomes, can have wide-ranging impacts on the variation of human phenotypes, including Mendelian and complex forms of diseases. These chromosomal alterations — such as duplications, deletions or copy-neutral loss-of-heterozygosity — are thus important forms of genetic variation for phenotyping populations of individuals as well as populations of cells. Indeed, copy number variants (CNVs) serve as hallmarks of critical changes in the development of particular diseases such as cancer and thus may be used as biomarkers. These CNVs may be either inherited (transmitted by germ cells, originating …

The Regulation Of Dna Methylation In Mammalian Development And Cancer, Nicolas Veland

Dissertations & Theses (Open Access)

DNA methylation is an essential epigenetic modification in mammals, as it plays important regulatory roles in multiple biological processes, such as gene transcription, maintenance of chromosomal structure and genomic stability, genomic imprinting, retrotransposon silencing, and X-chromosome inactivation. Dysregulation of DNA methylation is associated with various human diseases. For example, cancer cells usually show global hypomethylation and regional hypermenthylation, which have been implicated in genomic instability and tumor suppressor silencing, respectively. Although great progress has been made in elucidating the biological functions of DNA methylation over the last several decades, how DNA methylation patterns and levels are regulated and dysregulated is …

Genotype-Specific Insertion Of Cytotoxic Genetic Elements Into Cancer Cells, Ryan Englander

University Scholar Projects

The new gene editing system CRISPR/Cas9, composed of a complex composed of a guide RNA and the Cas9 endonuclease, promises to revolutionize biological research and potentially allow clinicians to directly modify patient DNA in vivo. While its applications in the treatment of genetic diseases and in modifying immune cells for immunotherapy are currently being explored, CRISPR/Cas9’s potential utility as a modular system for targeting tumor-specific mutated sequences has not as of yet been explored. While CRISPR/Cas9 is specific enough to target small insertions and deletions or gross chromosomal rearrangements, it is not specific enough to reliably restrict editing to …

Studies Of Norspermidine Uptake In Drosophila Suggest The Existence Of Multiple Polyamine Transport Pathways, Michael Dieffenbach

Honors Undergraduate Theses

Polyamines are a class of essential nutrients involved in many basic cellular processes such as gene expression, cell proliferation, and apoptosis. Without polyamines, cell growth is delayed or halted. Cancerous cells require an abundance of polyamines through a combination of synthesis and transport from the extracellular environment. An FDA-approved drug, D,L-α-difluoromethylornithine (DFMO), blocks polyamine synthesis but is ineffective at inhibiting cell growth due to polyamine transport. Thus, there is a need to develop drugs that inhibit polyamine transport to use in combination with DFMO. Surprisingly, little is known about the polyamine transport system in humans and other eukaryotes. Understanding the …

Characterization Of Staphylococcal Nuclease And Tudor Domain Containing Protein 1 (Snd1) As A Molecular Target In Hepatocellular Carcinoma And Non-Alcoholic Steatohepatitis, Nidhi H. Jariwala

Theses and Dissertations

CHARACTERIZATION OF STAPHYLOCOCCAL NUCLEASE AND TUDOR DOMAIN CONTAINING PROTEIN 1 (SND1) AS A MOLECULAR TARGET IN HEPATOCELLULAR CARCINOMA AND NON-ALCOHOLIC STEATOHEPATITIS

Nidhi Jariwala, PhD

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Integrative Life Sciences

Virginia Commonwealth University, 2017

Devanand Sarkar, M.B.B.S., PhD.

Associate Professor, Department of Human and Molecular Genetics

Virginia Commonwealth University

Richmond, Virginia

SND1, a subunit of the miRNA regulatory complex RISC, has been implicated as an oncogene in hepatocellular carcinoma (HCC). Oncoprotein SND1 regulates gene expression at a post-transcriptional level in multiple cancers including hepatocellular carcinoma (HCC). …

Re-Contacting Cancer Genetic Counseling Patients: Expectations Of Patients And Physicians, Zoe Elizabeth Siegel

Theses and Dissertations

The landscape of cancer genetic counseling and testing is rapidly evolving. Genetic testing technology is improving, management guidelines are evolving, and genetic testing options are expanding. These frequent updates to the components of cancer genetics have increased the complexity of managing patient care over time. In particular, this raises questions on the duty to re-contact patients as new information becomes available. This study explored healthcare providers’ duty to re-contact through the interests and expectations of patients, including which circumstances warrant re-contacting, which healthcare provider is responsible for re-contacting the patient, and the preferred method of re-contacting. Physicians’ opinions on whether …