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- All Subjects: Cancer
- Creators: Lake, Douglas
Description
Programmed cell death ligand-1 (PD-L1) is an overexpressed protein on many tumor cell types. PD-L1 is involved in normal immune regulation, playing an important role in self-tolerance and controlling autoimmunity. However, ligation of PD-L1 to PD-1 on activated T cells leads to tumor-mediated T cell suppression. Inhibiting the PD-1/PD-L1 pathway has emerged as an effective target for anti-tumor immunotherapies. Monoclonal antibodies (mAbs) targeting tumor-associated antigens such as PD-L1 have proven to be effective checkpoint blockades, improving therapeutic outcomes for cancer patients and receiving FDA approval as first line therapies for some cancers. A single chain variable fragment (scFv) is composed of the variable heavy and light chain regions of a mAb, connected by a flexible linker. We hypothesized that scFv proteins based on the published anti-PD-L1 monoclonal antibody sequences of atezolizumab and avelumab would bind to cell surface PD-L1. Four single chain variable fragments (scFvs) were constructed based on the sequences of these mAbs. PCR was used to assemble, construct, and amplify DNA fragments encoding the scFvs which were subsequently ligated into a eukaryotic expression vector. Mammalian cells were transfected with the scFv and scFv-IgG plasmids. The scFvs were tested for binding to PD-L1 on tumor cell lysates by western blot and to whole tumor cells by staining and flow cytometry analysis. DNA sequence analysis demonstrated that the scFv constructs were successfully amplified and cloned into the expression vectors and recombinant scFvs were produced. The binding capabilities of the scFvs constucts to PD-L1 protein were confirmed by western blot and flow cytometry analysis. This lead to the idea of constructing a CAR T cell engineered to target PD-L1, providing a possible adoptive T cell immunotherapy.
ContributorsPfeffer, Kirsten M. (Author) / Lake, Douglas (Thesis director) / Ho, Thai (Committee member) / Hastings, Karen (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Each family approaches a cancer diagnosis differently. While some families pursue traditional treatments to the fullest extent, others attempt to refuse chemotherapy, often in favor of alternative medicines. When the patient is a minor, his or her parents have the authority to make medical decisions on their behalf, and this authority is constitutionally protected and socially upheld. However, when the decision to forgo chemotherapy does not comply with minimum standard of care and puts the minor's life in danger, legal action can and has been taken to force the minor to undergo chemotherapy. Legal precedent and biomedical ethics principles guide the decision-making process of the physicians and judges involved, although there is no official framework by which to prioritize these principles. Neglect and abuse procedures, as well as capacity determinations, mature minor doctrines, and religious convictions, add complexity to each forced chemotherapy case. These complexities were explored through the context of four case studies: Cassandra Callendar, who was not granted mature minor status and was forced into treatment by the Connecticut Supreme court; Starchild Abraham Cherrix, who was allowed to pursue the alternative Hoxsey therapy with the consent of his parents and the local court; Dennis Lindberg, a 14-year-old Jehovah's Witness who was permitted to refuse blood transfusions under the Mature Minor Doctrine; and Daniel Hauser, a developmentally delayed teen who was forced to undergo therapy against his parents' religious convictions. In the analysis and comprehensive comparison of these cases, it was concluded that an attempt to establish a protocol by which to determine the ethics of forcing chemotherapy, while well-intended, would ultimately be ineffective and extremely complex. Thus, each forced chemotherapy case must be evaluated on an individual basis.
ContributorsNelson, Sarah Gabrielle (Author) / Hendrickson, Kirstin (Thesis director) / Lynch, John (Committee member) / Jaramillo, Andres (Committee member) / School of Molecular Sciences (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Chemotherapy refers to the use of chemical agents to inhibit or stop the growth of rapidly dividing cancer cells. There are many side effects of systemic chemotherapy, which are caused because the drug not only kills cancer cells but healthy cells as well (American Cancer Society, 2017). Common side effects include fatigue, hair loss, bruising/ bleeding, infection, anemia, nausea and vomiting, appetite changes, constipation, diarrhea, oral sores, nerve and muscle pain, dry skin and color change, kidney dysfunction, weight loss, cognitive difficulties, mood changes, sexual dysfunction, and fertility problems (American Cancer Society, 2017). Research shows that complementary and alternative medicine (CAM) may help relieve some of the side effects of chemotherapy. Examples of CAM include herbal medicine, dietary supplements, acupuncture, yoga, Tai Chi, massage, electromagnetic therapy, meditation, biofeedback, music, dance, and guided imagery (Johns Hopkins Medicine, 2017). The aim of this creative project was to design a third-party website to provide information to patients undergoing chemotherapy and their family members regarding the use of CAM for the treatment of chemotherapy-induced side effects. Rationale for this project stemmed from a preliminary research step. We analyzed and coded for presence or absence of CAM-specific information on the websites of 20 National Cancer Institute-designated comprehensive cancer centers across the United States. Fifty percent of websites were double-coded. Inter-rater reliabilities (kappa values) for coding of the presence or absence of specific CAM therapies ranged from 0.38 for acupuncture to 1.00 for exercise and yoga, expressive arts, and herbs (mean kappa = 0.75). Fourteen of the 20 websites mentioned meditation or mindfulness; 13 mentioned nutrition; 12 mentioned acupuncture; 11 mentioned exercise or yoga; 11 mentioned massage; 8 mentioned expressive arts; and 3 mentioned herbs. Frequencies for presence of either a description of the specific CAM therapy or an explanation of how the therapy works were lower. We then conducted a literature review using PUBMED to find peer-reviewed research on the efficacy of the previously described seven CAM therapies. The literature search focused on systematic reviews and meta-analyses published within the past 10 years. Based on the literature obtained, we created summaries of the scientific evidence for each CAM therapy. This information is now provided on our third-party website in tabular form with summative statements. The website describes in lay language: chemotherapy, chemotherapy side effects, CAM, seven specific CAM therapies, and evidence for the efficacy or lack thereof of each. Per the American Nurses Association (2015), it is our responsibility to advocate for our patients through education and holistic treatment. The role of the nurse is to educate the patient about treatment options; however, it is not within the nurse's scope of practice to prescribe a treatment. As such, this website should not be viewed as a prescription for CAM therapies, but instead as a user-friendly and easily accessible resource for informed decision-making regarding the adjunctive use of CAM therapies.
ContributorsNichols, Abrianna (Co-author) / Varosky, Maxwell (Co-author) / Langer, Shelby (Thesis director) / Morris, Brenda (Committee member) / Arizona State University. College of Nursing & Healthcare Innovation (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Exosomes have been known to secrete an increased amount of miRNA and noncoding genes that are abnormally expressed in various cancer subtypes. Thus, they may be an early marker for pediatric cancer types that are more difficult to diagnosis without invasive techniques, and may also help identify progression of the disease. In the project, six types of pediatric cancer cell lines, along with their extracted exosomes, were analyzed and tested for different monoclonal antibodies through western blot analysis. The genes EWS-FLI1 and FGFR4 were also identified in some cancer cell lines through Reverse-Transcriptase Polymerase Chain Reaction analysis (RT-PCR). The results were indicative of similar protein markers being found in both the originating cells and their corresponding exosomes.
ContributorsKaur Bhinder, Harsimran (Author) / Lake, Douglas (Thesis director) / Azorsa, David (Committee member) / Barrett, The Honors College (Contributor)
Created2017-12
Description
As advanced as current cancer therapeutics are, there are still challenges that need to be addressed. One of them is the non-specific killing of normal cells in addition to cancerous cells. Ideal cancer therapeutics should be targeted specifically toward tumor cells. Due to the robust self-assembly and versatile addressability of DNA-nanostructures, a DNA tetrahedron nanostructure was explored as a drug carrier. The nanostructure can be decorated with various molecules to either increase immunogenicity, toxicity, or affinity to a specific cell type. The efficiency of the specific binding and internalization of the chosen molecules was measured via flow cytometry. Using a murine B cell lymphoma as the model system, several targeting molecules have been evaluated for their specific binding and induced internalization of DNA nanostructures, including an anti-Igκ antibody, an idiotype-binding peptide, and a g-quadruplex nucleolin specific aptamer. It was found that adding the anti-Igκ antibody appeared to provide increased binding and facilitated cellular internalization. Also, it was found that the presence of CpG appeared to aid in the binding of nanostructures decorated with other molecules, as compared to nanostructures without CpG. The g-quadruplex aptamer thought to specifically bind cancer cells that overexpress nucleolin was tested and found to have better binding to cells when linked to the nanostructure than when alone. The drug doxorubicin was used to load the DNA-nanostructure and attempt to inhibit cancer cell growth. The DNA-nanostructure has the benefit of being self-assembled and customizable, and it has been shown to bind to and internalize into a cancer cell line. The next steps are to test the toxicity of the nanostructure as well as its specificity for cancerous cells compared to noncancerous cells. Furthermore, once those tests are completed the structure’s drug delivery capacity will be tested in tumor bearing mice. The DNA-nanostructure exhibits potential as a cancer specific therapeutic.
ContributorsGomez, Amber Marie (Author) / Chang, Yung (Thesis director) / Anderson, Karen (Committee member) / Liu, Xiaowei (Committee member) / Sanford School of Social and Family Dynamics (Contributor) / School of Molecular Sciences (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Cancer is one of the leading causes of death in the world and represents a tremendous burden on patients, families and societies. S. Typhimurium strains are specifically attracted to compounds produced by cancer cells and could overcome the traditional therapeutic barrier. However, a major problem with using live attenuated Salmonella as anti-cancer agents is their toxicity at the dose required for therapeutic efficacy, but reducing the dose results in diminished efficacy. In this project, we explored novel means to reduce the toxicity of the recombinant attenuated Salmonella by genetically engineering those virulence factors to facilitate maximal colonization of tumor tissues and reduced fitness in normal tissues. We have constructed two sets of Salmonella strains. In the first set, each targeted gene was knocked out by deletion of the gene. In the second set, the predicted promoter region of each gene was replaced with a rhamnose-regulated promoter, which will cease the synthesis of these genes in vivo, a rhamnose-free environment.
ContributorsBenson, Lee Samuel (Author) / Kong, Wei (Thesis director) / Martin, Thomas (Committee member) / Lake, Douglas (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / Center for Infectious Diseases and Vaccinology (Contributor) / School of Life Sciences (Contributor)
Created2013-05
Description
The long-term survival of patients with glioblastoma multiforme is compromised by the tumor's proclivity for local invasion into the surrounding normal brain. These invasive cells escape surgery and display resistance to chemotherapeutic- and radiation-induced apoptosis. We have previously shown that tumor necrosis factor-like weak inducer of apoptosis (TWEAK), a member of the tumor necrosis factor superfamily, can stimulate glioma cell invasion and survival via binding to the fibroblast growth factor-inducible 14 (Fn14) receptor and subsequent activation of the Rac1/NF-kappaB pathway. In addition, we have reported previously that Fn14 is expressed at high levels in migrating glioma cells in vitro and invading glioma cells in vivo. Here we demonstrate that TWEAK can act as a chemotactic factor for glioma cells, a potential process to drive cell invasion into the surrounding brain tissue. Specifically, we detected a chemotactic migration of glioma cells to the concentration gradient of TWEAK. Since Src family kinases (SFK) have been implicated in chemotaxis, we next determined whether TWEAK:Fn14 engagement activated these cytoplasmic tyrosine kinases. Our data shows that TWEAK stimulation of glioma cells results in a rapid phosphorylation of the SFK member Lyn as determined by multiplex Luminex assay and verified by immunoprecipitation. Immunodepletion of Lyn by siRNA oligonucleotides suppressed the chemoattractive effect of TWEAK on glioma cells. We hypothesize that TWEAK secretion by cells present in the glioma microenvironment induce invasion of glioma cells into the brain parenchyma. Understanding the function and signaling of the TWEAK-Fn14 ligand-receptor system may lead to development of novel therapies to therapeutically target invasive glioma cells.
ContributorsJameson, Nathan Meade (Author) / Anderson, Karen (Thesis director) / Lake, Douglas (Committee member) / Tran, Nhan (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2013-05
Description
Due to the Covid-19 pandemic, healthcare professionals including occupational therapy practitioners (OTPs) were required to transition to working utilizing an online-service delivery model called telehealth. The use of telehealth for occupational therapy (OT) sessions was limited prior to the pandemic, and this shift required OTPs to provide services in ways many had never experienced. The purpose of this study was to identify how the transition to telehealth impacted OTPs and their ability to provide proper care to the pediatric population via telehealth. The final analytic sample included 32 female OTPs who worked with the pediatric population. Results from qualitative and quantitative analyses showed that OTPs had positive feelings toward using telehealth and that the telehealth modality had a moderate impact on their job performance. The areas that pediatric OTPs want to be addressed included technology and internet issues, lack of parent involvement, decreased quality of care, inaccessibility of materials, decreased attention span and increased distractions, and lack of general knowledge about telehealth among clients, parents, and professionals. Despite these drawbacks, a positive theme emerged that the telehealth model is good for current circumstances. The results show telehealth is a positive experience for OTPs and allows OT to be more accessible to their clients. Implications for increasing education for healthcare professionals, clients, and parents/guardians to make telehealth accessible to clients on a large scale are discussed.
ContributorsMulvaney, Kaitlin Marie (Author) / Bryce, Crystal (Thesis director) / Seeley, Bridget (Committee member) / Sanford School of Social and Family Dynamics (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Quiescin sulfhydryl oxidase 1 (QSOX1) is a highly conserved disulfide bond-generating enzyme that represents the ancient fusion of two major thiol-disulfide oxidoreductase gene families: thioredoxin and ERV. QSOX1 was first linked with cancer after being identified as overexpressed in pancreatic ductal adenocarcinoma (but not in adjacent normal ductal epithelia, infiltrating lymphocytes, or chronic pancreatitis). QSOX1 overexpression has been confirmed in a number of other histological tumor types, such as breast, lung, kidney, prostate, and others. Expression of QSOX1 supports a proliferative and invasive phenotype in tumor cells, and its enzymatic activity is critical for promoting an invasive phenotype. An in vivo tumor growth study utilizing the pancreatic tumor cell line MIAPaCa-2 containing a QSOX1-silencing shRNA construct revealed that QSOX1 expression supports a proliferative phenotype. These preliminary studies suggest that suppressing the enzymatic activity of QSOX1 could represent a novel therapeutic strategy to inhibit proliferation and invasion of malignant neoplasms.
The goal of this research was to identify and characterize biologically active small molecule inhibitors for QSOX1. Chemical inhibition of QSOX1 enzymatic activity was hypothesized to reduce growth and invasion of tumor cells. Recombinant QSOX1 was screened against libraries of small molecules using an enzymatic activity assay to identify potential QSOX1 inhibitors. Two lead QSOX1 inhibitors were confirmed, 2-phenyl-1, 2-benzisoselenazol-3-one (ebselen), and 3-methoxy-n-[4-(1 pyrrolidinyl)phenyl]benzamide. The biological activity of these compounds is consistent with QSOX1 knockdown in tumor cell lines, reducing growth and invasion in vitro. Treatment of tumor cells with these compounds also resulted in specific ECM defects, a phenotype associated with QSOX1 knockdown. Additionally, these compounds were shown to be active in pancreatic and renal cancer xenografts, reducing tumor growth with daily treatment. For ebselen, the molecular mechanism of inhibition was determined using a combination of biochemical and mass spectrometric techniques. The results obtained in these studies provide proof-of-principle that targeting QSOX1 enzymatic activity with chemical compounds represents a novel potential therapeutic avenue worthy of further investigation in cancer. Additionally, the utility of these small molecules as chemical probes will yield future insight into the general biology of QSOX1, including the identification of novel substrates of QSOX1.
The goal of this research was to identify and characterize biologically active small molecule inhibitors for QSOX1. Chemical inhibition of QSOX1 enzymatic activity was hypothesized to reduce growth and invasion of tumor cells. Recombinant QSOX1 was screened against libraries of small molecules using an enzymatic activity assay to identify potential QSOX1 inhibitors. Two lead QSOX1 inhibitors were confirmed, 2-phenyl-1, 2-benzisoselenazol-3-one (ebselen), and 3-methoxy-n-[4-(1 pyrrolidinyl)phenyl]benzamide. The biological activity of these compounds is consistent with QSOX1 knockdown in tumor cell lines, reducing growth and invasion in vitro. Treatment of tumor cells with these compounds also resulted in specific ECM defects, a phenotype associated with QSOX1 knockdown. Additionally, these compounds were shown to be active in pancreatic and renal cancer xenografts, reducing tumor growth with daily treatment. For ebselen, the molecular mechanism of inhibition was determined using a combination of biochemical and mass spectrometric techniques. The results obtained in these studies provide proof-of-principle that targeting QSOX1 enzymatic activity with chemical compounds represents a novel potential therapeutic avenue worthy of further investigation in cancer. Additionally, the utility of these small molecules as chemical probes will yield future insight into the general biology of QSOX1, including the identification of novel substrates of QSOX1.
ContributorsHanavan, Paul D (Author) / Lake, Douglas (Thesis advisor) / LaBaer, Joshua (Committee member) / Mangone, Marco (Committee member) / Borges, Chad (Committee member) / Arizona State University (Publisher)
Created2015
Description
Quiescin Sulfhydryl Oxidase 1 (QSOX1) generates disulfide bonds in its client substrates via oxidation of free thiols. Localized to the Golgi and secreted, QSOX1 helps to fold proteins into their active form. Early work with QSOX1 in cancer began with the identification of a peptide from the long form of QSOX1 in plasma from patients with pancreatic ductal adenocarcinoma. Subsequent work confirmed the overexpression of QSOX1 in numerous cancers in addition to pancreatic, including those originating in the breast, lung, brain, and kidney. For my work, I decided to answer the question, “How does inhibition of QSOX1 effect the cancer phenotype?” To answer this I sought to fulfill the following goals A) determine the overexpression parameters of QSOX1 in cancer, B) identify QSOX1 small molecule inhibitors and their effect on the cancer phenotype, and C) determine potential biological effects of QSOX1 in cancer. Antibodies raised against rQSOX1 or a peptide from QSOX1-L were used to probe cancer cells of various origins for QSOX1 expression. High-throughput screening was utilized to identify 3-methoxy-n-[4(1pyrrolidinyl)phenyl]benzamide (SBI-183) as a lead inhibitor of QSOX1 enzymatic activity. Characterization of SBI-183 activity on various tumor cell lines revealed inhibition of viability and invasion in vitro, and inhibition of growth, invasion, and metastasis in vivo, a phenotype that was consistent with QSOX1 shKnockdown cells. Subsequent work identified 3,4,5-trimethoxy-N-[4-(1-pyrrolidinyl)phenyl]benzamide (SPX-009) as an SBI-183 analog with stronger inhibition of QSOX1 enzymatic activity, resulting in a more potent reduction in tumor invasion in vitro. Additional work with QSOX1 shKnockdown and Knockout (KO) cell lines confirmed current literature that QSOX1 is biologically active in modulation of the ECM. These results provide evidence for the master regulatory role of QSOX1 in cancer, making it an attractive chemotherapeutic target. Additionally, the small molecules identified here may prove to be useful probes in further elucidation of QSOX1 tumor biology and biomarker discovery.
ContributorsFifield, Amber (Author) / Lake, Douglas (Thesis advisor) / Ho, Thai (Committee member) / Rawls, Jeffery (Committee member) / Borges, Chad (Committee member) / Arizona State University (Publisher)
Created2020