Matching Items (342)
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The focus of this project was to look at alternative treatments for endocrine resistant breast cancer (ERBC), which are breast cancers that have become resistant to hormone therapies such as Tamoxifen or aromatase inhibitors. The first part of this project involves investigating the relationship between histone de-acetylase inhibitor Vorinostat and

The focus of this project was to look at alternative treatments for endocrine resistant breast cancer (ERBC), which are breast cancers that have become resistant to hormone therapies such as Tamoxifen or aromatase inhibitors. The first part of this project involves investigating the relationship between histone de-acetylase inhibitor Vorinostat and Tamoxifen in MCF7 G11 cells, Tamoxifen resistant sub-clones, according to the PSOC Time grant. The second part involves targeting the androgen receptor (AR) in MCF7 sub-clones with AR antagonists, Bicalutamide and MDV3100, and investigating the possible usage of AR as a biomarker, due to over-expression of AR in ERBC, in accordance with the Mayo ASU Seed Grant.
The synergistic effects between Vorinostat and Tamoxifen observed through a phase II study on breast cancer patients resistant to hormone therapy may involve more than the modulation of ER-alpha to reverse Tamoxifen resistance in ERBC cells. RT-qPCR of genes expressed in Tamoxifen resistant cells, trefoil factor 1(TFF1) and v-myc avian myelocytomatosis viral oncogene homolog (MYC), were evaluated along with ESR1 and Diablo as a control. MYC was observed to have increased expression in the treated cells, whereas the other genes had a decrease in their expression levels after the cells were treated for 3 days with Vorinostat IC30 of 1 µM. As for targeting the AR, MCF7 Tamoxifen sensitive and resistant cells were not affected by the AR antagonists to determine an IC50. The cell viability for all MCF7 sub-clones only decreased for high concentrations of 5.56 µM - 50 µM in Bicalutamide and 16.67 µM – 50 µM of MDV1300. Furthermore, hormone depletion of MCF7 G11 Tamoxifen resistant sub-clones did not show a great response to DHT stimulation or the AR antagonists. In the RT-qPCR, the MCF7 G11 cells showed an increase in mRNA expression for ER, AR, and PR after 4 hours of treatment with estradiol. As for the DHT treatment, ER, AR, PR, and PSA had a minimal increase in the fold change, but the fold change in AR was less than in the estradiol treatment. The Mayo Clinic will investigate the possible usage of AR as a biomarker through immunohistochemistry.
ContributorsVorachitti, Merica (Author) / LaBaer, Joshua (Thesis director) / Anderson, Karen (Committee member) / Gonzalez, Laura (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
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A coincidence reporter construct, consisting of the p21-promoter and two luciferase genes (Firefly and Renilla), was constructed for the screening of drugs that might inhibit Olig2's tumorigenic role in glioblastoma. The reporter construct was tested using an Olig2 inhibitor, HSP990, as well as short hairpin RNA targeting Olig2. Further confirmatory

A coincidence reporter construct, consisting of the p21-promoter and two luciferase genes (Firefly and Renilla), was constructed for the screening of drugs that might inhibit Olig2's tumorigenic role in glioblastoma. The reporter construct was tested using an Olig2 inhibitor, HSP990, as well as short hairpin RNA targeting Olig2. Further confirmatory analysis is needed before the reporter cell line is ready for high-throughput screening at the NIH and lead compound selection.
ContributorsCusimano, Joseph Michael (Author) / LaBaer, Joshua (Thesis director) / Mangone, Marco (Committee member) / Mehta, Shwetal (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
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The pathogenesis of type 1 diabetes (T1D) is still not fully understood in the scientific community. Evidence has shown that viral infections are one of the important environmental factors associated with the disease development. Seven of the top T1D related viruses were selected to study the prevalence of viral humoral

The pathogenesis of type 1 diabetes (T1D) is still not fully understood in the scientific community. Evidence has shown that viral infections are one of the important environmental factors associated with the disease development. Seven of the top T1D related viruses were selected to study the prevalence of viral humoral response in T1D patients using our innovative protein array platform called Nucleic Acid Programmable Protein Array (NAPPA). In this study, each viral gene was individually captured using various PCR based techniques, cloned into a protein expression vector, and assembled as the first version of T1D viral protein array. Humoral responses of IgG, IgA, and IgM were examined. Although each class of immunoglobulin generated a wide-range of reactivity, responses to various viral proteins from different proteins were observed. In summary, we captured most of the T1D related viral genes, established viral protein expression on the protein array, and displayed the serum response on the viral protein array. The successful progress will help to fulfill the long term goal of testing the viral infection hypothesis in T1D development.
ContributorsDavis, Amy Darlene (Author) / LaBaer, Joshua (Thesis director) / Qiu, Ji (Committee member) / Desi, Paul (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2013-05
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Protein AMPylation is a recently discovered and relatively unstudied post-translational modification (PTM). AMPylation has previously been shown to play an important role in metabolic regulation and host pathogenesis in bacteria, but the recent identification of potential AMPylators across many species in every domain of life has supported the possibility that

Protein AMPylation is a recently discovered and relatively unstudied post-translational modification (PTM). AMPylation has previously been shown to play an important role in metabolic regulation and host pathogenesis in bacteria, but the recent identification of potential AMPylators across many species in every domain of life has supported the possibility that AMPylation could be a more fundamental and physiologically significant regulatory PTM. For the first time, we characterized the auto-AMPylation capability of the human protein SOS1 through in vitro AMPylation experiments using full-length protein and whole-domain truncation mutants. We found that SOS1 can become AMPylated at a tyrosine residue possibly within the Cdc25 domain of the protein, the Dbl homology domain is vital for efficient auto-AMPylation activity, and the C-terminal proline-rich domain exhibits a complex regulatory function. The proline-rich domain alone also appears to be capable of catalyzing a separate, unidentified covalent self-modification using a fluorescent ATP analogue. Finally, SOS1 was shown to be capable of catalyzing the AMPylation of two endogenous human protein substrates: a ubiquitous, unidentified protein of ~49kDa and another breast-cancer specific, unidentified protein of ~28kDa.
ContributorsOber-Reynolds, Benjamin John (Author) / LaBaer, Joshua (Thesis director) / Borges, Chad (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2014-05
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AMPylation is a post-translation modification that has an important role in the survival of many bacterial pathogens by affecting the host cell's molecular signaling. In the course of studying this intercellular manipulation, there has only been modest progression in the identification of the enzymes with AMPylation capabilities (AMPylators) and their

AMPylation is a post-translation modification that has an important role in the survival of many bacterial pathogens by affecting the host cell's molecular signaling. In the course of studying this intercellular manipulation, there has only been modest progression in the identification of the enzymes with AMPylation capabilities (AMPylators) and their respective targets. The reason for these minimal developments is the inability to analyze a large subset of these proteins. Therefore, to increase the efficiency of the identification and characterization of the proteins, Yu et al developed a high-throughput non-radioactive discovery platform using Human Nucleic Acid Programmable Protein Arrays (NAPPA) and a validation platform using bead-based assays. The large-scale unbiased screening of potential substrates for two bacterial AMPylators containing Fic domain, VopS and IbpAFic2, had been performed and dozens of novel substrates were identified and confirmed. With the efficiency of this method, the platform was extended to the identification of novel substrates for a Legionella virulence factor, SidM, containing a different adenylyl transferase domain. The screening was performed using NAPPA arrays comprising of 10,000 human proteins, the active AMPylator SidM, and its inactive D110/112A mutant as a negative control. Many potential substrates of SidM were found, including Rab GTPases and non-GTPase proteins. Several of which have been confirmed with the bead-based AMPylation assays.
ContributorsGraves, Morgan C. (Author) / LaBaer, Joshua (Thesis director) / Qiu, Ji (Committee member) / Yu, Xiaobo (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2013-05
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The purpose of this project was to identify proteins associated with the migration and invasion of non-transformed MCF10A mammary epithelial cells with ectopically expressed missense mutations in p53. Because of the prevalence of TP53 missense mutations in basal-like and triple-negative breast cancer tumors, understanding the effect of TP53 mutations on

The purpose of this project was to identify proteins associated with the migration and invasion of non-transformed MCF10A mammary epithelial cells with ectopically expressed missense mutations in p53. Because of the prevalence of TP53 missense mutations in basal-like and triple-negative breast cancer tumors, understanding the effect of TP53 mutations on the phenotypic expression of human mammary epithelial cells may offer new therapeutic targets for those currently lacking in treatment options. As such, MCF10A mammary epithelial cells ectopically overexpressing structural mutations (G245S, H179R, R175H, Y163C, Y220C, and Y234C) and DNA-binding mutations (R248Q, R248W, R273C, and R273H) in the DNA-binding domain were selected for use in this project. Overexpression of p53 in the mutant cell lines was confirmed by western blot and q-PCR analysis targeting the V5 epitope tag present in the pLenti4 vector used to transduce TP53 into the mutant cell lines. Characterization of the invasion and migration phenotypes resulting from the overexpression of p53 in the mutant cell lines was achieved using transwell invasion and migration assays with Boyden chambers. Statistical analysis showed that three cell lines—DNA-contact mutants R248W and R273C and structural mutant Y220C—were consistently more migratory and invasive and demonstrated a relationship between the migration and invasion properties of the mutant cell lines. Two families of proteins were then explored: those involved in the Epithelial-Mesenchymal Transition (EMT) and matrix metalloproteinases (MMPs). Results of q-PCR and immunofluorescence analysis of epithelial marker E-cadherin and mesenchymal proteins Slug and Vimentin did not show a clear relationship between mRNA and protein expression levels with the migration and invasiveness phenotypes observed in the transwell studies. Results of western blotting, q-PCR, and zymography of MMP-2 and MMP-9 also did not show any consistent results indicating a definite relationship between MMPs and the overall invasiveness of the cells. Finally, two drugs were tested as possible treatments inhibiting invasiveness: ebselen and SBI-183. These drugs were tested on only the most invasive of the MCF10A p53 mutant cell lines (R248W, R273C, and Y220C). Results of invasion assay following 30 μM treatment with ebselen and SBI-183 showed that ebselen does not inhibit invasiveness; SBI-183, however, did inhibit invasiveness in all three cell lines tested. As such, SBI-183 will be an important compound to study in the future as a treatment that could potentially serve to benefit triple-negative or basal-like breast cancer patients who currently lack therapeutic treatment options.
ContributorsZhang, Kathie Q (Author) / LaBaer, Joshua (Thesis director) / Anderson, Karen (Committee member) / Gonzalez, Laura (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2015-05
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The potential empowerment of the UN System as a result of the Responsibility to Protect doctrine requires an examination of what it could mean for both state sovereignty and the authority of the UN Security Council. I argue that the Security Council is already a sovereign body within the international

The potential empowerment of the UN System as a result of the Responsibility to Protect doctrine requires an examination of what it could mean for both state sovereignty and the authority of the UN Security Council. I argue that the Security Council is already a sovereign body within the international system that would be greatly empowered by the implementation of the Responsibility to Protect doctrine and the veto reform efforts of the Accountability, Transparency and Coherence (ACT) Group. I rely on Carl Schmitt’s influential definition of sovereignty and his key takeaways regarding the 1919 German constitution to illustrate the existence of two distinct levels of Schmittian-like sovereigns in the international system: state sovereigns and representative sovereigns. I will then describe the authority and structure of the Security Council followed by a brief case study of the North Atlantic Treaty Organization’s (NATO) intervention in Kosovo as an example of how real-life situations challenge the Security Council’s ability to exercise its role as a representative sovereign, including a discussion about how it can either fail to act or choose not to act and the difference between them. Afterwards, I will discuss the Responsibility to Protect doctrine and how it expands the relative power of representative sovereignty at the cost of reducing the relative power of state sovereignty, culminating in a discussion of what attempts to reform the veto power on the Security Council may do to the Council’s sovereignty. Finally, I will conclude with a discussion of the key takeaways of this paper and some further considerations.

ContributorsVega, Cameron Johnathan (Author) / Perez, Luke (Thesis director) / Levin, Irina (Committee member) / Historical, Philosophical & Religious Studies (Contributor, Contributor) / School of Politics and Global Studies (Contributor, Contributor, Contributor, Contributor) / School of Civic & Economic Thought and Leadership (Contributor) / School of Social Transformation (Contributor) / Historical, Philosophical & Religious Studies, Sch (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The United States’ War on Drugs declared in 1971 by President Richard Nixon and revamped by President Reagan in the 1980s has been an objectively failed initiative with origins based in racism and oppression. After exploring the repercussions of this endeavor for societies and individuals around the world, global researchers

The United States’ War on Drugs declared in 1971 by President Richard Nixon and revamped by President Reagan in the 1980s has been an objectively failed initiative with origins based in racism and oppression. After exploring the repercussions of this endeavor for societies and individuals around the world, global researchers and policymakers have declared that the policies and institutions created to fight the battle have left devastation in their wake. Despite high economic and social costs, missed opportunities in public health and criminal justice sectors, and increasing limits on our personal freedoms, all the measures taken to eradicate drug abuse and trafficking have been unsuccessful. Not only that, but militarized police tactics, mass incarceration, and harsh penalties that stifle opportunities for rehabilitation, growth, and change disproportionately harm poor and minority communities. <br/>Because reform in U.S. drug policy is badly needed, the goals of America’s longest war need to be reevaluated, implications of the initiative reexamined, and alternative strategies reconsidered. Solutions must be propagated from a diverse spectrum of contributors and holistic understanding through scientific research, empirical evidence, innovation, public health, social wellbeing, and measurable outcomes. But before we can know where we should be headed, we need to appreciate how we got to where we are. This preliminary expository investigation will explore and outline the history of drug use and prohibition in the United States before the War on Drugs was officially declared. Through an examination of the different patterns of substance use, evolving civil tolerance of users, racially-charged anti-drug misinformation/propaganda campaigns, and increasingly restrictive drug control policies, a foundation for developing solutions and strengths-based strategies for drug reform will emerge.

ContributorsSherman, Brooke (Author) / Jimenez-Arista, Laura (Thesis director) / Mitchell, Ojmarrh (Committee member) / College of Integrative Sciences and Arts (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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I conducted a literature review of articles pertaining to the history and treatment of rats. After outlining all of the relevant connections, I argue that as a result of people's conceptions about rats, rats do not receive the same respect and protections afforded other animals, such as cats and dogs,

I conducted a literature review of articles pertaining to the history and treatment of rats. After outlining all of the relevant connections, I argue that as a result of people's conceptions about rats, rats do not receive the same respect and protections afforded other animals, such as cats and dogs, in the laboratory and beyond. I present both negative and positive conceptions about rats and the realities of these conceptions. Finally, I talk about the changes that need to take place in laboratory research, why animals are still used in research today, and the alternatives that exist to animal models.

Created2021-05
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Urban encroachment into traditional snake territories has long been underway; likely increasing snake sightings in urban neighborhoods. With increasing overlap, I ask if the perceptions of snakes are actually influencing urban residents to say that snakes are a significant problem in their neighborhood today? I was interested in finding out

Urban encroachment into traditional snake territories has long been underway; likely increasing snake sightings in urban neighborhoods. With increasing overlap, I ask if the perceptions of snakes are actually influencing urban residents to say that snakes are a significant problem in their neighborhood today? I was interested in finding out whether or not there would be a positive correlation between the perception of snakes being a problem within a neighborhood and the actual number of sightings recorded. To address this, I used survey responses from 2017 regarding the risk perception of snakes from twelve neighborhoods within Maricopa County. These responses were then compared to the number of snake sightings within those same neighborhoods over a span of ten years using community science data from iNaturalist. The average results of the people who took the survey perceived that snakes were not a problem in their neighborhood. It was also found that in the outlying areas closer to natural snake habitat (desert preserves), a positive correlation between a higher survey response and a higher number of snake sightings could be seen. Overall, the conclusion of the data revealed that the perceptions of residents did not align with the actual number of snake sightings.

ContributorsMiranda, Caroline (Author) / Bateman, Heather (Thesis director) / Brown, Jeffrey (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05