Diseases Commons^™

Repurposing Metformin And Antifolates For The Treatment Of Hepatocellular Carcinoma, Sherouk Mohamed Tawfik

Theses and Dissertations

Hepatocellular carcinoma (HCC), one of the most prevalent types of cancers worldwide, continues to maintain high levels of resistance to standard therapy. As clinical data revealed poor response rates, the need for developing new methods has increased to improve the overall wellbeing of patients with HCC. Due to its safety, wide availability and previously reported anti-cancer effects, metformin (MET) serves to be a possible therapeutic agent when combined with other well-known anti-cancer agents. The aim of this study was to investigate the potential anti-cancer effects of MET, an anti-diabetic agent, when combined with two antifolate drugs: trimethoprim (TMP) or methotrexate …

Crosstalk Between Hippo And Rb Tumour Suppressor Pathways In Ovarian Cancer, Fatmata Sesay

Theses and Dissertations

The cell cycle is a highly regulated process that ensures the timely and accurate division of cells. Events of the normal cell cycle fall under two categories - positive and negative regulatory mechanisms. The first category, positive regulatory machinery, includes active protein complexes of cyclins in association with their partnering cyclin-dependent kinases (cyclin/CDK), which mediate series of phosphorylation events that relay a cell cycle progression from one stage to the next. The second category, the negative regulatory mechanisms, include the checkpoint controls consisting of the retinoblastoma (RB) family of proteins, some of which can form a transcriptional repressor complex DREAM. …

Human Papillomavirus 16 E2 Regulates Host Cell Pathways Important For Cancer Progression And Treatment Sensitivity Which May Contribute To Cancer Outcomes, Christian Fontan

Theses and Dissertations

Human papillomaviruses (HPVs) are causative agents in around 5% of all cancers, including cervical and oropharyngeal. A feature of HPV cancers is their better clinical outcome compared with non-HPV anatomical counterparts. In turn, the presence of E2 predicts a better clinical outcome in HPV-positive cancers; the reason(s) for the better outcome of E2-positive patients is not fully understood.

Previously, we demonstrated that HPV16 E2 regulates host gene transcription that is relevant to the HPV16 lifecycle in N/Tert-1 cells. One of the genes repressed by E2 and the entire HPV16 genome in N/Tert-1 cells is TWIST1. In these studies, we demonstrate …

Stat5a Regulation By Serine Phosphorylation In Breast Cancer, Alicia E. Woock

Theses and Dissertations

The neuroendocrine hormone prolactin (PRL) and its cognate receptor (PRLr) have been implicated in the pathogenesis of breast cancer. PRL signaling relies on activating kinases such as the tyrosine kinase Jak2 and serine/threonine kinases ERK1/2, NEK3, PI3K, and AKT. In the canonical pathway of PRL signaling, JAK2 phosphorylates the transcription factor STAT5a at tyrosine residue 694 (pY694-STAT5a), preceding STAT5a nuclear translocation and transcriptional activity. However, STAT5a exists with functional duality as a transcription factor, having both pro-differentiative and pro-proliferative target genes. Other STAT family members (STATs 1, 3, and 6) have been shown to have transcriptional activity in the un-tyrosine-phosphorylated …

Investigating The Role Of Oncogene C-Terminal Binding Protein (Ctbp) In Pancreatic Ductal Adenocarcinoma, Kranthi Kumar Chougoni

Theses and Dissertations

The transcriptional coregulator CtBP2 has been implicated as an oncogene in colon, prostate, breast and ovarian cancers. Previously, we reported overexpression of CtBP2 in human PDAC specimens. However, its exact role in PDAC is still unclear. In the current study, we attempt to delineate the oncogenic role CtBP2 in PDAC growth and metastasis. Using an orthotopic syngeneic pancreatic tumor mouse model (CKP), we found that deletion of Ctbp2 decreases PDAC tumor growth, proliferation, metastasis, EMT and significantly prolongs survival. Further, we identified significant downregulation of Erbb3 mRNA levels upon deletion of Ctbp2 in CKP PDAC cells As ErbB3 signaling was …

From Bedside To Bench: Use Of Patient-Derived Xenograft Models To Develop Novel Therapeutic Strategies For Triple-Negative Breast Cancer, Tia H. Turner

Theses and Dissertations

Triple-negative breast cancer (TNBC) is a clinically aggressive disease that is associated with bleak outcomes due to its metastatic propensity, frequent failure to respond to chemotherapy, and lack of alternative treatment options. Despite decades of major translational research efforts, there has been very little success thus far in the development of effective targeted therapies for this disease. It is imperative to develop novel therapeutic strategies to improve patient outcomes, as well as minimize the toxicity associated with standard-of-care chemotherapeutics. Given that metastatic disease accounts for the vast majority of TNBC-related deaths, a better understanding of therapeutic responses within common sites …

The Role Of Syndecan-1 And Extracellular Vesicles In Breast Cancer Brain Metastasis, Megan R. Sayyad

Theses and Dissertations

Breast cancer metastasizes to the brain in 15-30% of all breast cancer cases, and metastasis is the predominant cause of breast cancer-related deaths. Patients with HER2-enriched and triple-negative breast cancers (TNBCs) are more likely to develop brain metastases. While targeted therapies exist for HER2-enriched breast cancers, there are no effective treatments for TNBCs. Thus, a greater understanding of how these cancers spread to the brain is critical. In order to spread to the brain, disseminated breast cancer cells must overcome 2 major steps—crossing the blood-brain barrier (BBB) and survival and successful colonization of the distinctive and mostly cellular brain environment. …

Novel Insights Into The Contribution Of Cellular Senescence To Cancer Therapy: Reversibility, Dormancy And Senolysis., Tareq Saleh

Theses and Dissertations

Cellular senescence a specialized form of growth arrest that contributes to the pathogenesis of several aging-related disorders including cancer. While by definition tumor cells are considered immortalized, they can undergo senescence when exposed to conventional and targeted cancer therapy. Therapy-Induced Senescence (TIS) represents a fundamental response to therapy and impacts its outcomes. However, TIS has been considered a positive therapeutic goal since senescent tumor cells are expected to enter a state of permanent growth abrogation. In this work we examined the hypothesis that a subpopulation of senescent cells can re-acquire proliferative potential after a state of senescent dormancy, indicating that …

Racial And Ethnic Differences In Receipt Of Immediate Breast Reconstruction Surgery: Do Hospital Characteristics Matter?, Jaya Shankar Khushalani

Theses and Dissertations

Immediate Breast Reconstruction Surgery (IBRS) is associated with better quality of life among women who undergo a mastectomy. Despite insurance coverage for IBRS, utilization of IBRS remains low. Data from publicly available sources for 2010-2012 are used to examine the association between hospital characteristics receipt of IBRS by patients. Minority-serving status, low bed size, for-profit ownership, non-teaching status, high competition, low density of plastic surgeons in the market and non-metropolitan location are associated with lower likelihood of receipt of IBRS.

Racial and ethnic minorities are less likely to receive IBRS. A mixed effects logistic regression model with interactions between Black/Hispanic …

Type 2 Immune Responses In The Context Of Helminth Infection, Asthma, Dendritic Cells, And Myeloid Derived Suppressor Cell Function, Sheela Ruby Damle

Theses and Dissertations

Type 2 (T_H2) immune responses evolved to respond to helminth parasite infections by the production of T_H2 cytokines, which stimulate anti-helminth immunity. Macrophage migration inhibitor factor (MIF) is a pleiotropic cytokine, which is produced by many cell types. We demonstrate that mice deficient in MIF have enhanced clearance of a helminth parasite. MIF deficiency in CD4⁺ T cells was found to be the most important for mediating parasite clearance. We mimicked MIF deficiency by administering an inhibitor of the MIF tautomerase activity, sulforaphane, and this also increased parasite clearance (Section I).

T_H2 immune …

The Impact Of Chemotherapy And Radiotherapy For Breast Cancer On Cognition And Functional Performance: A Comparative Analysis Of Survey Data Taken At Three Time Points Post-Treatment, Ann Marie Potter

Theses and Dissertations

Cognitive impairment related to treatment for breast cancer, affects as many as 75% of patients in study samples (Jansen, Cooper, Dodd & Miaskowski, 2011). Deficits in the cognitive domains of short-term memory, attention, speed of information processing, judgment, reasoning, spatial attention, and verbal memory have been documented. The extent to which these deficits impact functional performance within this population has not yet been quantified. The purpose of this study was to investigate the impact of breast cancer on self-reported cognition and functional performance in the six months post-completion in two groups of breast cancer survivors, a chemotherapy group and chemotherapy …

Dual Pi3k/Mtor Inhibition With Bez235 Augments The Therapeutic Efficacy Of Doxorubicin In Cancer Without Influencing Cardiac Function, David E. Durrant

Theses and Dissertations

Cancer continues to be a leading cause death in the United States despite improved treatments. Cancerous lesions form after acquiring oncogenic driver mutations or losing tumor suppressor function in normal cells. Traditional therapies have included use of genotoxic substances that take advantage of the increased growth rate and loss of tumor suppressor function to cause cell death. One such drug is the anthracycline antibiotic doxorubicin (DOX). DOX interchelates into DNA and disrupts transcriptional machinery while also poisoning topoisomerase II. This results in single and double stranded DNA breaks, which if severe enough leads to either necrotic or apoptotic cell death. …

Novel Therapeutic Strategies For Pancreatic Cancer, Bridget A. Quinn

Theses and Dissertations

Pancreatic cancer is a devastating disease that leaves patients with a very poor prognosis and few therapeutic options. Many of the treatment options available are the same that have been used for almost 2 decades. There is a dire need for both novel treatments for this disease as well as novel strategies of treatment. This body of work will introduce and provide evidence in support of a novel combination therapy for pancreatic cancer treatment, a novel strategy of modifying currently used chemotherapeutics for pancreatic cancer therapy, and a novel transgenic preclinical mouse model of pancreatic cancer. Sabutoclax, an antagonist of …

Sildenafil And Celecoxib Interact To Kill Breast Cancer Cells, Brittany Binion

Theses and Dissertations

Breast cancer is the second most commonly diagnosed cancer among American women and is responsible for the second highest number of cancer-related deaths. Targeted therapeutic agents sildenafil, a phosphodiesterase type 5 inhibitor, and celecoxib, a cyclooxygenase-2 inhibitor, have been used individually in conjunction with other chemotherapeutic agents to enhance cell killing in a variety of cancers. Sildenafil when combined with traditional chemotherapeutic drugs, such as the taxanes and anthracyclines, or celecoxib combined with traditional hormone therapies have been used to increase cytotoxicity and cell killing. The data presented here demonstrates that the novel combination of sildenafil and celecoxib work together …