Matching Items (10)
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- All Subjects: Breast Cancer
- All Subjects: immunotherapy
- Creators: Anderson, Karen
Description
Background: High risk types of human papillomavirus (HPV) are known to cause cancer, including cervical (99%) and oropharyngeal cancer (70%). HPV type 16 is the most common subtype. Three antigens that are critical for integration or tumor progression are E2, E6 and E7. In this study, we developed a systematic approach to identify naturally-processed HPV16-derived HLA class I epitopes for immunotherapy development. Methods: K562 cells, which lack HLA expression, were transduced with each HPV16 antigen using lentivirus and supertransfected with HLA-A2 by nucleofection. Stable cell lines expressing each antigen were selected for and maintained throughout the investigation. In order to establish a Gateway-compatible vector for robust transient gene expression, a Gateway recombination expression cloning cassette was inserted into the commercial Lonza pMAX GFP backbone, which has been experimentally shown to display high transfection expression efficiency. GFP was cloned into the vector and plain K562 cells were transfected with the plasmid by nucleofection. Results: Expression of K562-A2 was tested at various time points by flow cytometry and A2 expression was confirmed. Protein expression was shown for the transduced K562 E7 by Western blot analysis. High transfection efficiency of the pMAX_GFP_Dest vector (up to 97% GFP+ cells) was obtained 48 hours post transfection, comparable to the commercial GFP-plasmid. Conclusion: We have established a rapid system for target viral antigen co-expression with single HLA molecules for analysis of antigen presentation. Using HPV as a model system, our goal is to identify specific antigenic peptide sequences to develop immunotherapeutic treatments for HPV-associated cancers.
ContributorsVarda, Bianca Marie (Author) / Anderson, Karen (Thesis director) / Borges, Chad (Committee member) / Krishna, Sri (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
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.
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
Description
Our goal was to design a method to express soluble folded major histocompatibility complex (MHC) proteins using human cell line HeLa lysate with the novel 1-Step Human In Vitro Protein Expression by Thermo Scientific in the presence of β2 microglobulin (β2m) and antigenic peptide.
We confirmed that the soluble protein MHC-A2.1 could be successfully attached to the Luminex magnetic beads and detected using the primary antibody anti-GST and the detection antibody goat mAb mouse PE. The average net MFI of the attached pA2.1-bead complex was 8182. Biotinylated A2.1 MHC complexes pre-folded with β2m and FLU M1 peptide (A2.1 monomers) were also successfully attached to Luminex magnetic beads and detected with BB7.2. The average net MFI of the detected A2.1 monmer-bead complexes was 318. The protein MHC complexes were multimerized on magnetic beads to create MHC tetramers and detected with BB7.2, PE labeled monoclonal antibody, via median fluorescent intensity with the Luminex platform. Varying protein, β2 microglobulin (β2m), and peptide concentrations were tested in a number of MHC-A2.1 protein refolding trials. Different antigenic peptides and attachment methods were also tested. However, none of the MHC-A2.1 protein folding and capture trials were successful. Although MHC-A2.1 complexes and recombinant MHC molecules could be attached to Luminex magnetic beads and be detected by Luminex arrays, soluble protein A2.1 could not be successfully expressed, refolded, captured onto Luminex beads, and detected. All refolding trials resulted in a net MFI of <25. The failed refolding and capture trials of A2.1 lead to the conclusion that human cell line HeLa lysate cannot be used to properly fold MHC molecules. However, efforts to refold the complexes onto Luminex magnetic beads are ongoing. We are also using the baculovirus expression system to refold soluble A2.1 lysate onto peptide-bead complexes.
We confirmed that the soluble protein MHC-A2.1 could be successfully attached to the Luminex magnetic beads and detected using the primary antibody anti-GST and the detection antibody goat mAb mouse PE. The average net MFI of the attached pA2.1-bead complex was 8182. Biotinylated A2.1 MHC complexes pre-folded with β2m and FLU M1 peptide (A2.1 monomers) were also successfully attached to Luminex magnetic beads and detected with BB7.2. The average net MFI of the detected A2.1 monmer-bead complexes was 318. The protein MHC complexes were multimerized on magnetic beads to create MHC tetramers and detected with BB7.2, PE labeled monoclonal antibody, via median fluorescent intensity with the Luminex platform. Varying protein, β2 microglobulin (β2m), and peptide concentrations were tested in a number of MHC-A2.1 protein refolding trials. Different antigenic peptides and attachment methods were also tested. However, none of the MHC-A2.1 protein folding and capture trials were successful. Although MHC-A2.1 complexes and recombinant MHC molecules could be attached to Luminex magnetic beads and be detected by Luminex arrays, soluble protein A2.1 could not be successfully expressed, refolded, captured onto Luminex beads, and detected. All refolding trials resulted in a net MFI of <25. The failed refolding and capture trials of A2.1 lead to the conclusion that human cell line HeLa lysate cannot be used to properly fold MHC molecules. However, efforts to refold the complexes onto Luminex magnetic beads are ongoing. We are also using the baculovirus expression system to refold soluble A2.1 lysate onto peptide-bead complexes.
ContributorsChang, Peter S (Author) / Anderson, Karen (Thesis director) / Chang, Yung (Committee member) / Sundaresan, Krishna (Committee member) / Barrett, The Honors College (Contributor) / T. Denny Sanford School of Social and Family Dynamics (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2013-05
Description
Background: Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer deaths in females worldwide, accounting for 23% of all new cancer cases and 14% of all total cancer deaths in 2008. Five tumor-normal pairs of primary breast epithelial cells were treated for infinite proliferation by using a ROCK inhibitor and mouse feeder cells. Methods: Raw paired-end, 100x coverage RNA-Seq data was aligned to the Human Reference Genome Version 19 using BWA and Tophat. Gene differential expression analysis was completed using Cufflinks and Cuffdiff. Interactive Genome Viewer was used for data visualization. Results: 15 genes were found to be down-regulated by at least one log-fold change in 4/5 of tumor samples. 75 genes were found to be down-regulated in 3/5 of our tumor samples by at least one log-fold change. 11 genes were found to be up-regulated in 4/5 of our tumor samples, and 68 genes were identified to be up-regulated in 3/5 of the tumor samples by at least one-fold change. Conclusion: Expression changes in genes such as AZGP1, AGER, ALG11, and S1007 suggest a disruption in the glycosylation pathway. No correlation was found between Cufflink's Her2 gene-expression and DAKO score classification.
ContributorsHernandez, Fernando (Author) / Anderson, Karen (Thesis director) / Mangone, Marco (Committee member) / Park, Jin (Committee member) / Barrett, The Honors College (Contributor) / Department of Information Systems (Contributor)
Created2013-05
Description
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
Description
The p53 gene functions as a tumor suppressor that inhibits proliferation, regulates apoptosis, DNA repair, and normal cell cycle arrest. Mutation of the p53 gene is linked to be prevalent in 50% of all human cancers. In this paper, we are exploring triple negative breast cancer and the effects of simvastatin on tumor growth and survival. Simvastatin is a drug that is primarily used to treat high cholesterol and heart disease. Simvastatin is unique because it is able to inhibit protein prenylation through regulation of the mevalonate pathway. This makes it a potential targeted drug for therapy against p53 mutant cancer. The mechanism behind this is hypothesized to be correlated to aberrant activation of the Ras pathway. The Ras subfamily functions to transcriptionally regulate cell growth and survival, and will therefore allow for a tumor to thrive if the pathway is continually and abnormally activated. The Ras protein has to be prenylated in order for activation of this pathway to occur, making statin drug treatment a viable option as a cancer treatment. This is because it acts as a regulator of the mevalonate pathway which is upstream of protein prenylation. It is thus vital to understand these pathways at both the gene and protein level in different p53 mutants to further understand if simvastatin is indeed a drug with anti-cancer properties and can be used to target cancers with p53 mutation. The goal of this project is to study the biochemistry behind the mutation of p53's sensitivity to statin. With this information we can create a possible signature for those who could benefit from Simvastatin drug treatment as a possible targeted treatment for p53 mutant cancers.
ContributorsGrewal, Harneet (Co-author) / Loo, Yi Jia Valerie (Co-author) / Anderson, Karen (Thesis director) / Blattman, Joseph (Committee member) / Ferdosi, Shayesteh (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Adaptive therapy utilizes competitive interactions between resistant and sensitive cells by keeping some sensitive cells to control tumor burden with the aim of increasing overall survival and time to progression. The use of adaptive therapy to treat breast cancer, ovarian cancer, and pancreatic cancer in preclinical models has shown significant results in controlling tumor growth. The adaptive therapy model comes from the integrated pest management agricultural strategy, predator prey model, and the unique intra- and inter-tumor heterogeneity of tumors. The purpose of this thesis is to analyze and compare gemcitabine dose response on hormone refractory breast cancer cells retrieved from mice using an adaptive therapy strategy with standard therapy treatment. In this study, we compared intermittent (drug holiday) adaptive therapy with maximum tolerated dose therapy. The MCF7 resistant cell lines to both fulvestrant and palbociclib were injected into the mammary fat pads of 8 weeks old NOD/SCID gamma (NSG) mice which were then treated with gemcitabine. Tumor burden graphs were made to track tumor growth/decline during different treatments while Drug Dose Response (DDR) curves were made to test the sensitivity of the cell lines to the drug gemcitabine. The tumor burden graphs showed success in controlling the tumor burden with intermittent treatment. The DDR curves showed a positive result in using the adaptive therapy treatment method to treat mice with gemcitabine. Due to some fluctuating DDR results, the sensitivity of the cell lines to gemcitabine needs to be further studied by repeating the DDR experiment on the other mice cell lines for stronger results.
ContributorsConti, Aviona Christina (Author) / Maley, Carlo (Thesis advisor) / Blattman, Joseph (Committee member) / Anderson, Karen (Committee member) / Arizona State University (Publisher)
Created2022
Description
The TP53 tumor suppressor gene is the most frequently mutated gene in human cancers. In the highly aggressive triple negative breast cancer (TNBC), TP53 is mutated in 80% of cases. TNBC lacks viable drug targets, resulting in a low prognosis (12.2% 5 year survivability rate). As such, the discovery of druggable targets in TNBC would be beneficial. Mutated p53 protein typically occurs as a missense mutation and often endows cancer cells with gain of function (GOF) properties by dysregulating metabolic pathways. One of these frequently dysregulated pathways is the Hippo/Yes-associated protein-1 (YAP1)/WW Domain Containing Transcription Regulator 1 (TAZ) tumor suppressor pathway. This study therefore analyzed the involvement of the Hippo/YAP1/TAZ pathway in p53-mediated breast cancer cell invasion. From an RNA-seq screen in MCF10A cell lines harboring different TP53 missense mutations, each with a differing invasive phenotype, components of the Hippo pathway were found to correlate with cell invasion. To this end, the active and inactive forms of YAP1 and TAZ were studied. Phosphorylated (inactive) YAP1 and TAZ are retained in the cytoplasm and eventually degraded. Unphosphorylated (active) YAP1 and TAZ translocate to the nucleus to activate TEAD-family transcription factors, inducing cell survival and proliferation genes leading to increased cell invasion. Using quantitative western blot analysis, it was found that inactive TAZ expression was lower in the most invasive cell lines and higher in the least invasive cell lines (p = 0.003). Moreover, the ratio of inactive TAZ protein to total TAZ protein was also shown to be predominantly lower in the invasive cell lines compared to the non-invasive lines (p = 0.04). Finally, active TAZ expression was primarily higher in p53-mutant invasive cell lines and lower in non-invasive p53 mutant cells. Additionally, although YAP1 and TAZ are thought to be functionally redundant, the pattern seen in TAZ was not seen in the YAP1 protein. Taken together, the results demonstrated here suggest that TAZ holds a more dominant role in governing TNBC cell invasion compared to YAP1 and further highlights TAZ as a potential therapeutic target in TNBC.
ContributorsGrief, Dustin (Author) / LaBaer, Joshua (Thesis advisor) / Anderson, Karen (Committee member) / Nikkhah, Mehdi (Committee member) / Arizona State University (Publisher)
Created2022
Description
Lung metastatic cancers represent a major challenge in both basic and clinical cancer research. The ability to treat lung metastases to date has been challenging, current treatment paradigms are a mix of classic radiotherapy, chemotherapies and tumor-targeted therapies, with no one treatment that is effective for all tumors. Oncolytic viruses (OVs) represent a new therapeutic modality for hard-to-treat tumors. However, major questions still exist in the field, especially around how to therapeutically arm and deliver OVs to sites of disseminated tumors. To address this need, oncolytic myxoma viruses (MYXV) that expresses TNF superfamily member transgenes (vMYX-hTNF or vMyx-mLIGHT) were tested in an immunocompetent syngeneic lung metastatic murine osteosarcoma model. Three versions of this model were used; 1-an early intervention model, 2-an established tumor model, defined by both average tumor burden and failure of anti-PD-L1 and vMyx-TNF monotherapies, and 3-a late-stage disease model, defined by the failure the combination of vMyx-hTNF/PBMCs and anti-PD-L1 therapy. These three models were designed to test different questions about therapeutic efficacy of armed MYXV and delivery of MYXV to lung metastases. In the early intervention model, vMyx-hTNF was found to be an effective therapy, especially when delivered by leukocyte carrier cells (either bone marrow or PBMCs). Next, the combination of immune checkpoint inhibitors, including anti-PD-L1, anti-PD-1 and anti-CTLA-4, with vMyx-TNF/PBMCs were found to increase efficacy in treated mice compared to monotherapies. The established model was used to test potential synergy of vMyx-hTNF with anti-PD-L1 therapy. This model was defined by the failure of the monotherapies, however, in combination, treated mice survived significantly longer, and had lower average tumor burden throughout. This model was also used to test tumor specific delivery using ex vivo loaded PBMCs as carrier cells. Using MYXV expressing Tdtomato, PBMCs were found to deliver MYXV to tumors more effectively than free virus. In the most stringent late-stage disease model, vMyx-mLIGHT/PBMCs and vMyx-mLIGHT/PBMCs plus anti-PD-1 were tested and found to be efficacious where combination vMyx-TNF/PBMCs plus PD-1 failed. These results taken together show that TNFSF arming of MYXV, especially when delivered by autologous PBMCs, represents a new potential treatment strategy for lung metastatic tumors.
ContributorsChristie, John Douglas (Author) / McFadden, Grant (Thesis advisor) / Blattman, Joseph (Committee member) / Jacobs, Bertram (Committee member) / Anderson, Karen (Committee member) / Arizona State University (Publisher)
Created2021
Description
Glioblastoma (GBM) is a highly invasive and deadly late stage tumor that develops from abnormal astrocytes in the brain. With few improvements in treatment over many decades, median patient survival is only 15 months and the 5-year survival rate hovers at 6%. Numerous challenges are encountered in the development of treatments for GBM. The blood-brain barrier (BBB) serves as a primary obstacle due to its innate ability to prevent unwanted molecules, such as most chemotherapeutics, from entering the brain tissue and reaching malignant cells. The GBM cells themselves serve as a second obstacle, having a high level of genetic and phenotypic heterogeneity. This characteristic improves the probability of a population of cells to have resistance to treatment, which ensures the survival of the tumor. Here, the development and testing of two different modes of therapy for treating GBM is described. These therapeutics were enhanced by pathogenic peptides known to improve entry into brain tissue or to bind GBM cells to overcome the BBB and/or tumor cell heterogeneity. The first therapeutic utilizes a small peptide, RVG-29, derived from the rabies virus glycoprotein to improve brain-specific delivery of nanoparticles encapsulated with a small molecule payload. RVG-29-targeted nanoparticles were observed to reach the brain of healthy mice in higher concentrations 2 hours following intravenous injection compared to control particles. However, targeted camptothecin-loaded nanoparticles were not capable of producing significant treatment benefits compared to non-targeted particles in an orthotopic mouse model of GBM. Peptide degradation following injection was shown to be a likely cause for reduced treatment benefit. The second therapeutic utilizes chlorotoxin, a non-toxic 36-amino acid peptide found in the venom of the deathstalker scorpion, expressed as a fusion to antibody fragments to enhance T cell recognition and killing of GBM. This candidate biologic, known as anti-CD3/chlorotoxin (ACDClx) is expressed as an insoluble protein in Nicotiana benthamiana and Escherichia coli and must be purified in denaturing and reducing conditions prior to being refolded. ACDClx was shown to selectively activate T cells only in the presence of GBM cells, providing evidence that further preclinical development of ACDClx as a GBM immunotherapy is warranted.
ContributorsCook, Rebecca Leanne (Author) / Blattman, Joseph N (Thesis advisor) / Sirianni, Rachael W. (Thesis advisor) / Mor, Tsafrir (Committee member) / Anderson, Karen (Committee member) / Arizona State University (Publisher)
Created2019