Cancer Biology Commons^™

Identification Of Important Regulators Of Colon Cancer Tumorigenesis By Functional Screening, Haowei Yi

Theses & Dissertations

TGFβ signaling is an important regulator in colon cancer. miRNAs regulate TGFβ signaling at multiple levels. In this study, through a functional screening, we identified miR-487b-3p and miR-656-3p, which modulate TGFβ effect in colon cancer cells. Further studies revealed that GRM3 and VGLUT3 are their respective targets.

GRM3, a Metabotropic glutamate receptor in glutamatergic pathway is significantly upregulated in majority of human colonic adenocarcinomas tested and colon cancer cell lines. Knockdown of GRM3 expression or inhibition of GRM3 activation in colon cancer cells reduces cell survival and anchorage-independent growth in vitro and inhibits tumor growth in vivo. Mechanistically, GRM3 …

Aberrant Glycosylation In Pancreatic Cancer Progression, Seema Chugh

Theses & Dissertations

Aberrant changes in O-glycosylation patterns underlie pancreatic ductal adenocarcinoma (PDAC) progression and metastasis. Glycosylation is a post-translational modification in which carbohydrate moieties are attached to the protein substrate. My dissertation is focused on mucin-type O-glycosylation, which is the predominant form of O-glycosylation and is regulated by a myriad of glycosyltransferases.

PDAC is one of the most lethal diseases and the mechanistic involvement of aberrant O-glycosylation in its progression and metastasis is unknown. The aberrant glycosylation refers to the appearance of unusual carbohydrate structures such as truncated carbohydrate antigens, often referred to as tumor-associated carbohydrate antigens.

In this dissertation, my goal …

Role Of Endothelin Axis In Pancreatic Tumor Microenvironment, Suprit Gupta

Theses & Dissertations

Endothelins (ETs) are a family of three 21 amino-acid vasoactive peptides ET-1, ET-2 and ET-3 that mediate their effects via two G-protein couple receptors ET_AR and ET_BR which are expressed on various cell types. Apart from their physiological role in vasoconstriction, there is emerging evidence supporting the role of endothelin axis (ET-axis) in cancer. Due to the expression of ET receptors on various cell-types, ET-axis can exert pleotropic effects and contribute to various aspects of cancer pathobiology. Several studies have provided a fragmented picture of the diverse roles or ET-axis in various tumors. However, the comprehensive …

The Role Of Ehd2 In Triple-Negative Breast Cancer Tumorigenesis And Progression, Timothy A. Bielecki

Theses & Dissertations

Triple-negative breast cancer (TNBC) comprises 10%-15% of all breast cancer cases, yet is clinically challenging due to lack of targeted therapies which leads to higher mortality. Molecular subtyping has identified the most aggressive subclasses of breast cancer to be enriched in components of caveolae. While caveolae have been linked to many biological processes, their precise role in TNBC is still poorly understood. EHD2, a member of the C-terminal EPS15-Homology Domain-containing (EHD) protein family, has emerged as a new regulator of caveolae dynamics and is essential to maintain a stable membrane pool of caveolae. Studies in model cells demonstrate that caveolae …

The Role Of Semaphorin 5a In Pancreatic Cancer Progression And Metastasis, Sugandha Saxena Dr.

Theses & Dissertations

Pancreatic cancer (PC) is an aggressive disease with an overall 5-year survival rate of less than 7%, statistics that have not changed in almost five decades. Metastasis is one of the leading causes of mortality in PC. Accumulating evidence suggests that axon guidance molecules, such as semaphorins, are involved in cancer progression, invasion, and metastasis. Recent genomic characterization of pancreatic ductal adenocarcinoma revealed aberration in axon guidance pathway genes as well. Previous reports from our laboratory have identified one such molecule Semaphorin5A (SEMA5A) as a putative cell adhesion molecule which is involved in organ-specific homing during PC metastasis. My dissertation …

Mapping The Interaction Between Lrrc59 And Cip2a Oncoprotein, Tamika C. Reed

Graduate School of Biomedical Sciences Theses and Dissertations

The oncogene cancerous inhibitor of protein phosphatase 2A (CIP2A) has been shown to promote oncogenesis through numerous protein-protein interactions. CIP2A was initially found to be a direct inhibitor of the PP2A tumor suppressor protein; however, new research has demonstrated that CIP2A can act independently of PP2A through protein-protein interactions resulting in deregulation of the cell cycle and the development of therapeutic drug resistance, tumorigenesis, and cell proliferation. It has been shown that leucine rich repeat containing 59 protein (LRRC59) binds to and is required for the nuclear translocation of CIP2A, thereby making this interaction a target for drug therapy. Thus, …

Characterization Of E-Cadherin Regulation In Response To Zeb1 Inhibition In Endometrial Cancer Cell Lines, Chidozie Paul Chukwu

Graduate School of Biomedical Sciences Theses and Dissertations

Epithelial to mesenchymal transition (EMT) is the process in which cells lose their epithelial structure during gastrulation. This process also affects the migration and movement of tumor cells and promotes invasion and metastases of endometrial carcinomas. Down-regulation of E-cadherin (CDH1) by transcription factors is the key target of EMT modulators and is achieved mainly by ZEB1 (zinc finger E-box binding homeobox 1). Current research looking at restoration of E-cadherin expression in vitro involves the use of small molecules such as histone deacetylase (HDAC) inhibitors and DNA methyltransferase inhibitors. Trichostatin A (TSA) and small interfering ribonucleic acid (siRNA) are tools that …

A Review Of The Signal Transduction Pathways Involved In Epithelial Mesenchymal Transition Induced In Breast Cancer Metastasis And Their Cross-Talks, Kasey Cervantes '17

Independent Study

Epithelial-Mesenchymal Transition (EMT) is a biological process utilized by epithelial cells to transform into motile mesenchymal cells, initiating metastasis in cancer. EMT is also utilized during development and wound healing [10]. This process allows for cancerous cells to detach themselves from their primary tumor and invade normal tissue in preferred organ sites, forming secondary tumors called metastases. Metastasis is very important in the progression of cancer in patients as it the process responsible for the mortality of patients through the collection of metastases that effect vital organs like the brain, lung, or immune system. The most common metastases for malignant …

Optimizing A Standard Fasting Time For 2-Nbdg Uptake Studies In Murine Breast Cancers, Andrew C. Briley

Biomedical Engineering Undergraduate Honors Theses

Recently, there has been a larger use of 2-NBDG, a fluorescent glucose analog, to study glucose uptake in different cell types. These cell types have ranged anywhere from bacteria to human cancer cells. However, there has yet to be a standard procedure and practice for using 2-NBDG. In this study, our goal is to create a standard fasting time for the cells before introducing 2-NBDG to them. This study uses 4T07 cells, a murine breast cancer cell line, to help optimize this fasting time. These cells were fasted at different time points in order to find the ideal fasting time. …

Mechanism Of Lck Activation In Driving Leukemia Cell Proliferation, Hannah E. Dobson

Senior Honors Projects

Leukemia is a type of cancer that develops in blood-forming tissues of the immune system. These tissues can include the bone marrow or sites within the lymphatic system such as the lymph nodes. Leukemia progresses from a mutational event within a white blood cell. Often this mutation alters the cell’s normal life cycle, resulting in uninhibited cell division and growth. With this uncontrolled cell proliferation, mutated white blood cells accumulate and begin interfering with the functioning of healthy cells.

Scientists are unsure of the exact mechanisms required for leukemia development. However, recently scientists identified four characteristic mutations in the protein …

Identifying The Signaling Mechanisms Of Egfr-Mediated Apoptosis., Nicole Marion Jackson

Electronic Theses and Dissertations

The Epidermal Growth Factor Receptor (EGFR) is a 170-kilodalton transmembrane protein that belongs to the ErbB family of receptor tyrosine kinases. Upon ligand-mediated activation, the EGFR is responsible for cell growth, proliferation, and tissue homeostasis; however, the EGFR is overexpressed in many human malignancies, including MDA-MB-468 cells, a metastatic breast epithelial cell line. Studies within this cell line, and other cell lines characterized with high EGFR levels, have shown that EGF stimulation results in the induction of apoptosis. However, the mechanisms and signaling effectors implicated in this process have yet to be elucidated. The overarching research goal of this dissertation …

Cyclin B1 Mediates The Effect Of Uchl1 In Promoting Cell Cycle Progression In Uterine Papillary Serous Carcinoma, Suet Ying Kwan

Dissertations and Theses (Open Access)

Uterine papillary serous carcinoma (UPSC) is an aggressive form of endometrial cancer with poor survival rates and a high risk of recurrence. The rarity of UPSC poses challenges to the discovery of novel targeted therapies. Therefore, the purpose of this dissertation was to identify novel therapeutic targets that could aid in the management of UPSC. To do so, we began with the relatively large cohort of UPSC cases in the TCGA data set, which was used to identify differentially expressed genes between UPSC and low-grade endometrioid endometrial carcinoma (EEC) and normal tissue.

We identified Ubiquitin Carboxyl-Terminal Hydrolase L1 (UCHL1 …

Fluorinated N,N'-Diarylureas As Novel Therapeutic Agents Against Cancer Stem Cells, Dasha E. Kenlan, Piotr G. Rychahou, Vitaliy M. Sviripa, Heidi L. Weiss, Chunming Liu, David S. Watt, B. Mark Evers

Markey Cancer Center Faculty Publications

Colorectal cancer is the second-leading cause of cancer-related mortality in the United States. More than 50% of patients with colorectal cancer will develop local recurrence or distant organ metastasis. Cancer stem cells play a major role in the survival and metastasis of cancer cells. In this study, we examined the effects of novel AMP-activated protein kinase (AMPK) activating compounds on colorectal cancer metastatic and stem cell lines as potential candidates for chemotherapy. We found that activation of AMPK by all fluorinated N,N-diarylureas (FND) compounds at micromolar levels significantly inhibited the cell-cycle progression and subsequent cellular proliferation. In addition, we demonstrated …

Paracrine Regulation Of Melanocyte Genomic Stability: A Focus On Nucleotide Excision Repair, Stuart Gordon Jarrett, Katharine Marie Carter, John August D'Orazio

Markey Cancer Center Faculty Publications

UV radiation is a major environmental risk factor for the development of melanoma by causing DNA damage and mutations. Resistance to UV damage is largely determined by the capacity of melanocytes to respond to UV injury by repairing mutagenic photolesions. The nucleotide excision repair (NER) pathway is the major mechanism by which cells correct UV photodamage. This multistep process involves the basic steps of damage recognition, isolation, localized strand unwinding, assembly of a repair complex, excision of the damage‐containing strand 3′ and 5′ to the photolesion, synthesis of a sequence‐appropriate replacement strand, and finally ligation to restore continuity of genomic …

Parp Inhibitor Upregulates Pd-L1 Expression And Enhances Cancer-Associated Immunosuppression, Shiping Jiao

Dissertations and Theses (Open Access)

With recent approvals for therapeutic antibodies that block CTLA4, PD-1 and PD-L1, immune checkpoints have emerged as new targets in cancer therapy. In addition, there is accumulating evidence highlighting the role of cancer-associated immunity in patient response to cytotoxic anticancer agents. Inhibitors of poly (ADP-ribose) polymerase (PARP) have shown substantial cytotoxic effects against tumors with defects in DNA damage responses. However, whether a crosstalk between PARP inhibition and immune checkpoints exists remains unclear. Here, it has been shown that PARP inhibitors (PARPis) upregulate PD-L1 expression in multiple cancer cell lines, human xenograft tumors, and syngeneic mouse tumors. Mechanistically, PARPi inactivates …

The Role Of The Diras Family Members In Regulating Ras Function, Cancer Growth And Autophagy, Margie Nicole Sutton

Dissertations and Theses (Open Access)

DIRAS3 is a maternally imprinted tumor suppressor gene that is downregulated by multiple mechanisms across several tumor types. When re-expressed, DIRAS3 decreases proliferation, inhibits motility, and induces autophagy and tumor dormancy. DIRAS3 encodes a 26 kDa small GTPase with 60% homology to Ras and Rap, differing from oncogenic Ras family members by a 34-amino acid N-terminal extension that is required for its tumor suppressive function in ovarian cancer. By assessing the structure-function relationship, I found that DIRAS3 inhibits Ras-induced transformation and is a natural antagonist of Ras/MAPK signaling. DIRAS3 binds directly to Ras and disrupts cluster formation inhibiting the activation …

Androgen Receptor And Prostate Cancer Cell Heterogeneity, Qu Deng

Dissertations and Theses (Open Access)

Androgen receptor (AR) plays an important role in prostate cancer (PCa) development and has been the main therapeutic target in advanced PCa. AR expression is heterogeneous in both primary PCa and castration resistant prostate cancer (CRPC). However, the functional significance of AR heterogeneity in regulating PCa biology and response to androgen/AR-targeted therapies remains unclear. The overarching hypothesis for my Ph.D is that AR heterogeneity contributes to PCa development, progression, and therapy resistance. A more specific postulate is that PCa cells expressing AR (i.e, AR⁺) and PCa cells expressing little AR (i.e, AR^-/lo) possess intrinsically distinct …

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

Dissertations and 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 …

Targeting Autophagy To Improve Efficacy Of Cdk4/6 Inhibition In Breast Cancer, Smruthi Vijayaraghavan

Dissertations and Theses (Open Access)

Deregulation of the cell cycle machinery is a hallmark of cancer, leading to aberrant proliferation and tumorigenesis. The crucial role of the CDK4/6-Cyclin D pathway has led to the development and FDA approval (palbociclib, ribociclib) of CDK4/6 inhibitors for the treatment of advanced estrogen receptor positive breast cancer. However, three major clinical challenges remain: i) adverse events leading to discontinuation of therapy and ii) lack of reliable biomarkers to identify responsive patients and iii) acquired resistance to CDK4/6 inhibitors. Previous in vitro studies have shown that palbociclib mediated CDK4/6 inhibition induces G1 arrest and senescence in ER+ breast cancer cells, …

Stromal Fibroblasts Restrain The Rate Of Colon Cancer Progression And Metastasis By Suppressing Regulatory T Cells And Colon Cancer Stem Cells, Changsoo Kwak

Dissertations and Theses (Open Access)

The initiation, progression, and metastasis of tumors involve not only cancer cells, but also the tumor microenvironment, which consists of immune or inflammatory cells, fibroblasts, endothelial cells, and extracellular matrix components (ECM). Fibroblasts are ubiquitous stromal cells that can influence other neighboring cell types through the secretion of chemokines, cytokines, ECM, ECM remodeling enzymes, and other metabolites. Myofibroblasts are a distinct subtype of fibroblasts characterized by expression α-smooth muscle actin (αSMA). These cells are a dominant component of the microenvironment, and a FSP1 and FAP could be a different clone of fibroblasts. Myofibroblasts also have been known to contribute to …