Genomics Commons^™

Genomic Characterization Of Adolescent And Young Adult Cancers: Investigation Of Ewing Sarcoma Susceptibility And Chornobyl Thyroid Tumors, Olivia Lee

Dissertations & Theses (Open Access)

Adolescent and young adult (AYA) cancers, diagnosed between the ages of 15 and 39, can exhibit distinctive genetic and molecular characteristics. Reported epidemiologic findings and treatment outcomes based on pediatric and adult cancer studies are often not suitable for application to the AYA population, underscoring the need for more thorough genomic research. Advances in sequencing technologies have enabled comprehensive analyses of complex genomic characteristics of AYA cancers, crucial for understanding the underlying biology of these malignancies. Here, I have utilized advanced sequencing techniques and integrated analytic approaches to describe important genomic features in two different AYA cancer types: Ewing Sarcoma …

Deephtlv: A Deep Learning Framework For Detecting Human T-Lymphotrophic Virus 1 Integration Sites, Johnathan Jia, Johnathan Jia

Dissertations & Theses (Open Access)

In the 1980s, researchers found the first human oncogenic retrovirus called human T-lymphotrophic virus type 1 (HTLV-1). Since then, HTLV-1 has been identified as the causative agent behind several diseases such as adult T-cell leukemia/lymphoma (ATL) and a HTLV-1 associated myelopathy or tropical spastic paraparesis (HAM/TSP). As part of its normal replication cycle, the genome is converted into DNA and integrated into the genome. With several hundreds to thousands of unique viral integration sites (VISs) distributed with indeterminate preference throughout the genome, detection of HTLV-1 VISs is a challenging task. Experimental studies typically use molecular biology …

Haplotype-Informed Allelic Imbalance Detection From Rna In Cancer, Zuhal Ozcan

Dissertations & Theses (Open Access)

Comprehensive genomic and transcriptomic characterization of tumors has uncovered enrichment for distinct aneuploidy and expression patterns, demonstrating the utility of molecular based classification of cancers and their subtypes. Existing cohorts with transcriptomic profiling from next-generation sequencing contain an untapped potential to also relate genomics with rich clinical phenotypes. Yet, derivation of somatic copy number and expression profiles from analyses of RNA has remained elusive. Further, DNA analysis in these cohorts is not always feasible due to limited tissue availability or financial constraints. Here, we present a statistical approach that overcomes these challenges using haplotype information to aid detection of somatic …

Decoding Copy Number Substructure And Evolution From Single Cell Genomics, Darlan Conterno Minussi

Dissertations & Theses (Open Access)

Aneuploidy is a prominent feature in Triple-Negative Breast Cancers (TNBC), however, the evolution of genotypes during tumor expansion remains poorly understood. The prevalent model of TNBC evolution is the Punctuated Copy Number Evolution (PCNE), in which tumors undergo a period of elevated genomic instability, acquiring complex genomic rearrangements within a short timeframe followed by clonal stasis. However, these observations rely on limited cell numbers and inherent experimental bias from first-generation single cell technologies. Therefore, the evolutionary trajectory after the punctuated burst remains unknown. To address this question, we sequenced 9,765 cells from 8 primary TNBCs and 6,413 cells from 4 …

Investigating The Ecology And Evolution Of Normal Breast Tissues And Breast Cancer With Single Cell Genomics, Tapsi Kumar, Tapsi Kumar

Dissertations & Theses (Open Access)

There is vast cellular heterogeneity in human breast tissues, with different transcriptional programs in the stromal, epithelial, and immune components, however, it remains unclear how their reprogramming and interplay leads to the progression of invasive phenotypes such as Triple- Negative Breast cancer (TNBC). To do define the microenvironmental alterations that occur during cancer, we first established a human breast cell atlas, a reference of normal breast cell types from disease free women. We profiled 535,941 cells from 62 women and 124,024 nuclei from 20 women revealing 11 major cell types and 52 cell states that reflect different biological functions that …

Computational Approaches To Understand Chemoresistance & Tumor Evolution Using Longitudinal Clinical Data And Lineage Tracing, Sahil Seth

Dissertations & Theses (Open Access)

Tumors are highly heterogeneous and dynamic, continually adapting and evolving in response to their microenvironment as well as external perturbations. Multi-region (spatial) and single cell sequencing has enabled us to anatomize the heterogeneity further and provide evidence of its association with chemo and drug resistance. To investigate this further we took two different approaches to understand the chemo-resistance, and functional heterogeneity in Triple negative breast cancer (TNBC) and Pancreatic ductal carcinoma in situ (PDAC) from an evolutionary perspective.

The first approach was to leverage tumor profiling from an ongoing randomized clinical trial in triple-negative breast cancer (ARTEMIS) to assess mechanisms …

An Investigation Of Epigenetic Mechanisms Driving The Biology Of Head And Neck Squamous Cell Carcinoma, Scot Carson Callahan

Dissertations & Theses (Open Access)

Head and neck squamous cell carcinoma (HNSCC) is the 6th most common cancer worldwide and is associated with significant morbidity and mortality. To date, the majority of work in the field has focused on genomic alterations such as mutations and copy number alterations. However, the clinical success of targeted therapies that exploit known genomic alterations, such as EGFR mutations, has remained mixed. Over the past decade, the importance of epigenetic regulators has come to the forefront, with the realization that many of these genes are mutated in cancer. Despite this realization, the role of epigenetics in regulating tumorigenesis, progression and …

Impact Of Intratumor Heterogeneity And The Tumor Microenvironment In Shaping Tumor Evolution And Response To Therapy, Akash Mitra

Dissertations & Theses (Open Access)

Intratumor heterogeneity (ITH) is a crucial challenge in cancer treatment. The genotypic and phenotypic heterogeneity underlying diverse cancer types leads to subclonal variation, which may result in mixed or failed response to therapy. The heterogeneity at the tumor level, along with the tumor microenvironment (TME), often shapes tumor evolution and ultimately clinical outcome. Given that modern treatment paradigms increasingly expose patients with metastatic disease to multiple treatment modalities through the course of their disease, there exists a need to characterize robust and predictive biomarkers of response to therapy. In order to accurately characterize tumor evolution, we need to account for …

Computational Approaches To Delineate Transcriptional And Functional Heterogeneity In Pancreatic Cancer, Sanjana Srinivasan

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is an incurable disease characterized by poor survival, dense desmoplastic stroma and activating mutations in KRAS (>90%). These tumors are highly complex ecosystems composed of molecularly distinct sub-populations that exhibit a spectrum of genetic features and associated phenotypes. Despite recent advances in the transcriptomic characterization of PDAC into at least two tumor subtypes, this alone has been insufficient to define more specific patterns of oncogenic dependency. To fully leverage advancements in next generation sequencing and functional genomics, we have sought to establish computational methodologies to aid in refined target discovery, and to develop a novel …

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, …

A Context-Forward In Vivo Functional Genomics Platform For Target Discovery And Establishing Vulnerability Context In Pancreatic Cancer, Johnathon Rose, Johnathon Lynn Rose

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with a very poor patient prognosis (5-year survival of ≤ 7%). While transcriptional profiling has aided in the classification of this disease into at least two broader subtypes, this alone has so far been insufficient to inform on more nuanced patterns of oncogenic dependency. We hypothesized that a more comprehensive and granular characterization of PDAC disease diversity is required to establish relevant context for targeted therapy. To this end, we sought to establish an integrated platform to: i) more comprehensively characterize differential oncogenic signaling across our tumor models, and ii) establish …

Decoding The Evolutionary Response To Prostate Cancer Therapy Using Plasma Genome Sequencing, Naveen Ramesh

Dissertations & Theses (Open Access)

Investigating genome evolution in response to therapy is difficult in human tissue samples due to the difficulty in accessing metastatic tumor sites and logistical challenges of collecting longitudinal samples. To overcome these issues, we developed an unbiased whole-genome plasma DNA sequencing approach called PEGASUS that concurrently measures genomic copy number and exome mutations from archival cryostored plasma samples. This approach was applied to study longitudinal blood plasma samples from prostate cancer patients. A molecular characterization of archival plasma DNA from 233 patients and genomic profiling of 101 patients identified clinical correlations of aneuploid plasma DNA profiles with poor survival, increased …

Identification Of Trim24 Domain Essentiality In Primary Trim24coe Carcinosarcoma Cell Lines, Cem Dede

Dissertations & Theses (Open Access)

Regulation of transcriptional control is a critical feature for organismal development and survival. Because of its effects on chromatin-controlled expression, disruptions of this delicately tuned mechanism are an important factor in development of tumorigenesis. Therefore, there is a growing interest in targeting these control mechanisms for their potential therapeutic values.

Our lab previously discovered the epigenetic regulator function of Tripartite motif protein 24 (TRIM24) through its H3K4me0 and H3K23ac dual histone signature reader function, its negative regulatory effect on the p53 tumor suppressor, in addition to its shown oncogenic driving capacity on immortalized mammary epithelial cells when overexpressed. Although TRIM24 …

Molecular Consequences Of High Taz Expression In Gliomas, Visweswaran Ravikumar

Dissertations & Theses (Open Access)

Diffuse high grade gliomas are complex and lethal neoplasms of the adult central nervous system that are driven by a range of genetic and epigenetic alterations. Molecular classification of these tumors has identified different transcriptional subtypes, the most notable being Proneural (PN) and Mesenchymal (MES) classes. The most aggressive forms of the disease have a Mesenchymal expression signature, with reported PN-to-MES transition occurring with tumor progression. Master regulatory analysis has identified the transcriptional co-activator TAZ (WWTR1) as a major driver of the MES transition. Overexpression of this single protein in glioma stem cells has been shown to drive a transition …

Improving Dbnsfp, Mingyao Lu

Dissertations & Theses (Open Access)

IMPROVING dbNSFP

Mingyao Lu, B.S.

Advisory Professor: Xiaoming Liu, Ph.D.

The analysis and interpretation of DNA variation are very important for the Whole Exome studies (WES). Genome research has focused on single nucleotide variants (SNVs). Since indels are as important as SNVs, especially indels in coding regions are often candidates of disease-causing variants, thus, it is necessary to expand the focus to include indel mutations.

The goal of my project is to provide an automatic annotation pipeline to the WES based disease studies project by extending the dbNSFP with a tool for automated indel annotation and deleteriousness prediction. The current …

Omics Approaches To Uncover Germline And Somatic Variation Underlying Inherited Sarcomagenesis, Justin Wong

Dissertations & Theses (Open Access)

Sarcomas are rare mesenchymal tumors, making up 15% of all childhood and 1% of all adult tumors. They account for a disproportionate share of mortality in young adults, and if left untreated, are highly likely to metastasize. However, sarcoma etiology is poorly understood, and having numerous histological subtypes has complicated elucidation. To better understand factors underlying sarcomagenesis, we leveraged two rare inherited cancer predisposition syndromes, Li-Fraumeni Syndrome (LFS), and LFS-like (LFSL), both with a high incidence of sarcomas. LFS is caused by mutations in the tumor suppressor gene TP53 (p53), but has variable and incomplete penetrance, suggesting additional acquired …

Genomic And Transcriptomic Landscape Of Colorectal Premalignancy, Kyle Chang

Dissertations & Theses (Open Access)

Colorectal cancer (CRC) is the third most commonly diagnosed cancer among men and women in the United States, with 3 to 5 percent of the cases diagnosed in the background of a hereditary form of the disease. Biologically, CRC is divided into two groups: microsatellite instable (MSI) and chromosomally unstable (CIN). Genomic and transcriptomic characterization of CRC has emerged from large-scale studies in recent years due to the advancement of next-generation sequencing technologies. These studies have identified key genes and pathways altered in CRC and provided insights to the discovery of therapeutic targets. Despite the wealth of knowledge acquired in …

Integrative Cancer Immunogenomic Analysis Of Serial Melanoma Biopsies Reveals Correlates Of Response And Resistance To Sequential Ctla-4 And Pd-1 Blockade Treatment, Whijae Roh

Dissertations & Theses (Open Access)

Melanoma is the most malignant form of skin cancer. The five-year survival rate for metastatic melanoma is 19.9%. Although targeted therapy of BRAF and MEK inhibitors were developed for melanoma, resistance to therapy is inevitable. Immune checkpoint blockade, which reverses the suppression of the immune system, on the other hand, has shown a durable response in 20-30% of patients with metastatic melanoma. However, more predictive and robust biomarkers of response to this therapy are still needed, and resistance mechanisms remain incompletely understood. To address this, we examined a cohort of metastatic melanoma patients treated with sequential checkpoint blockade against cytotoxic …

Non-Coding Rnas Identify The Intrinsic Molecular Subtypes Of Muscle-Invasive Bladder Cancer, Andrea E. Ochoa

Dissertations & Theses (Open Access)

NON-CODING RNAS IDENTIFY THE INTRINSIC MOLECULAR SUBTYPES OF MUSCLE-INVASIVE BLADDER CANCER

Andrea Elizabeth Ochoa, B.S.

Advisory Professors: David J. McConkey, Ph.D. and Joya Chandra, Ph.D.

There has been a recent explosion of genomics data in muscle-invasive bladder cancer (MIBC) to better understand the underlying biology of the disease that leads to the high amount of heterogeneity that is seen clinically. These studies have identified relatively stable intrinsic molecular subtypes of MIBC that show similarities to the basal and luminal subtypes of breast cancer. However, previous studies have primarily focused on protein-coding genes or DNA mutations/alterations.

There is emerging evidence implicating …

Statistical Methods For Two Problems In Cancer Research: Analysis Of Rna-Seq Data From Archival Samples And Characterization Of Onset Of Multiple Primary Cancers, Jialu Li

Dissertations & Theses (Open Access)

My dissertation is focused on quantitative methodology development and application for two important topics in translational and clinical cancer research.

The first topic was motivated by the challenge of applying transcriptome sequencing (RNA-seq) to formalin-fixation and paraffin-embedding (FFPE) tumor samples for reliable diagnostic development. We designed a biospecimen study to directly compare gene expression results from different protocols to prepare libraries for RNA-seq from human breast cancer tissues, with randomization to fresh-frozen (FF) or FFPE conditions. To comprehensively evaluate the FFPE RNA-seq data quality for expression profiling, we developed multiple computational methods for assessment, such as the uniformity and continuity …

Development Of An In Silico Kir Genotyping Algorithm And Its Application To Population And Cancer Immunogenetic Analyses, Howard Rosoff

Dissertations & Theses (Open Access)

Gene content determination and variant calling in the complex KIR genomic region are useful for immune system function analysis, pathogenesis and disease risk factor elucidation, immunotherapy development, evolutionary investigations, and human migration modeling. Sequence-specific oligonucleotide and sequence-specific primer PCR methods are the de facto standards for KIR presence/absence identification, but the current platforms are unsuitable for SNP calling, impractical for KIR typing large cohorts of DNA samples, and inapplicable for typing repositories in which sequence data, but not cells or cell analytes, are available. Alternative typing methods, such as in silico sequence-based typing, can address the problems associated with amplicon-based …

Genomic Drivers Of Cutaneous Squamous Cell Carcinoma Development, Vida Chitsazzadeh

Dissertations & Theses (Open Access)

Skin cancer is the most common malignancy in humans. Annually, in U.S. there are over 3 million cases with an estimated overall economic impact of $2 billion. Cutaneous Squamous Cell Carcinoma (cuSCC) comprises 15-20% of all skin cancers. cuSCC has the best-defined progression from a distinct precancerous lesion, the Actinic Keratosis (AK), to invasive cuSCC. Destructive therapies for AK treatment must be used repetitively, causing significant morbidity. There is a tremendous need for targeted diagnostics and therapy for AKs, representing an important opportunity for secondary skin cancer prevention. Our knowledge of the molecular and cellular events that lead to the …

Accurate Mutation Annotation And Functional Prediction Enhance The Applicability Of -Omics Data In Precision Medicine, Tenghui Chen

Dissertations & Theses (Open Access)

Clinical sequencing has been recognized as an effective approach for enhancing the accuracy and efficiency of cancer patient management and therefore achieve the goals of personalized therapy. However, the accuracy of large scale sequencing data in clinics has been constrained by many different aspects, such as clinical detection, annotation and interpretation of the variants that are observed in clinical sequencing data. In my Ph.D thesis work, I mainly investigated how to comprehensively and efficiently apply high dimensional -omics data to enhance the capability of precision cancer medicine. Following this motivation, my dissertation has been focused on two important topics in …

Investigating Metastatic Lineage In Colorectal Cancer By Single Cell Dna Sequencing, Marco Leung

Dissertations & Theses (Open Access)

Metastasis is the primary cause of human cancer deaths. Patients with metastatic colorectal cancer (mCRC) show only an 11% 5-year survival rate, compared to those without local or distant metastases (92% 5-year survival rate). Understanding the CRC tumor evolution may provide valuable insights on how to improve treatment in patients with mCRC. However, the genomic basis of metastasis has been difficult to study, in part due to the extensive intratumor heterogeneity at both the primary and metastatic tumor sites, and the low frequency of subclones with metastatic potential. Previous studies have applied conventional bulk next-generation sequencing (NGS) methods, which have …

Detection Of Genes Influencing Chronic And Mendelian Disease Via Loss-Of-Function Variation, Alexander H. Li

Dissertations & Theses (Open Access)

A typical human exome harbors dozens of loss-of-function (LOF) variants predicted to severely disrupt or abolish gene function. These variants are enriched at the extremely rare end of the allele frequency spectrum (< 0.1%), suggesting purifying selection against these sites. However, most previous population-based sequencing studies have not included analysis of genotype-phenotype relationships with LOF variants. Thus, the contribution of LOF variation to health and disease within the general population remains largely uncharacterized.

Using whole exome sequence from 8,554 participants in the Atherosclerosis Risk in Communities (ARIC) study, we explored the impact of LOF variation on a broad spectrum of human phenotypes. First, we selected 20 common chronic disease risk factor phenotypes and performed gene-based association tests. Analysis of this sample verified two relationships in well-studied genes (PCSK9 and APOC3) and identified eight new loci. Novel relationships included …

Identification Of Familial Wilms Tumor Predisposition Genes Using Whole Genome Sequencing, Timothy B. Palculict

Dissertations & Theses (Open Access)

Wilms tumor, a childhood tumor arising from undifferentiated renal mesenchyme, is diagnosed in North America at a frequency of 1 in 10,000 live births and accounts for 5% of all pediatric cancers. The etiology of Wilms tumor is heterogeneous with multiple genes known to have an effect on Wilms tumor development; however, these genes are rarely associated with familial Wilms tumor. Gene mutations in WT1, WTX, CTNNB1 and TP53 are observed in a third of sporadic tumors, while the causative gene(s) responsible for familial Wilms tumor are largely unknown. Approximately 2% of Wilms tumor patients have a family …

Genomic Characterization Of Polyps In Familial Adenomatous Polyposis Patients And Identification Of Candidate Chemopreventive Drugs, Francis A. San Lucas

Dissertations & Theses (Open Access)

Familial adenomatous polyposis (FAP) is an autosomal dominant disease characterized by APC germline mutations and the development of hundreds to thousands of premalignant adenomas in the gastrointestinal tract at a young age. If left untreated, these patients inevitably develop colon cancer (CRC) and small bowel tumors. We performed exome sequencing of samples from 12 FAP patients to characterize adenomas and to identify candidate genes of adenoma development that may serve as potential targets for chemoprevention drug development. From each patient, a blood and at least one polyp were sequenced with a total of 25 polyps analyzed. In some cases, normal …

Genetic Predictors Of Metabolic Side Effects Of Diuretic Therapy, Jorge L. Del Aguila

Dissertations & Theses (Open Access)

Thiazide diuretics are a recommended first-line monotherapy for hypertension (i.e.SBP>140 mmHg or DBP>90 mmHg). Even so, diuretics are associated with adverse metabolic side effects, such as hyperlipidemia, hyperglycemia and hypokalemia which increase the risk of developing type II diabetes. This thesis used three analytical strategies to identify and quantify genetic factors that contribute to the development of adverse metabolic effects due to thiazide diuretic treatment. I performed a genome-wide association study (GWAS) and meta-analysis of the change in fasting plasma glucose and triglycerides in response to HCTZ from two different clinical trials: the Pharmacogenomic Evaluation of Antihypertensive Responses …

Introducing A Novel Method For Genetic Analysis Of Autism Spectrum Disorder, Sepideh Nouri

Dissertations & Theses (Open Access)

Autism is a spectrum of neurological disorders that is characterized by repetitive and stereotyped behaviors, lack of social skills in verbal and non-verbal communications, and intellectual disability. Recent statistics shows that 1 out of every 88 children in the US is affected by autism.

In this thesis, I first review previous studies on genetic association analyses of autism spectrum disorder. A large number of these studies fall into two categories: Genome Wide Association Studies (GWAS) and sequencing studies. Although GWAS are able to identify multiple common risk variants associated with different diseases, these common variants explain only a small portion …