Medicine and Health Sciences Commons^™

Targeting Neuronal Nitric Oxide Synthase (Nnos) For Melanoma Treatment, Shirley Tong

Pharmaceutical Sciences (PhD) Dissertations

Human cutaneous melanoma is the most aggressive form of skin cancer and the incidence rates have continued to increase over the years. Neuronal nitric oxide synthase (nNOS) produces nitric oxide (NO) has been found to be overexpressed in human melanoma and the expression of nNOS is induced by interferon-gamma (IFN-γ). In our studies, nNOS has been implicated in IFN-γ-stimulated melanoma progression and the inhibition of nNOS using novel inhibitors effectively inhibited IFN-γ-stimulated tumor growth in a xenograft mouse model. Programmed death-ligand 1 (PD-L1) is overexpressed in melanoma and plays an important role in suppressing the immune system ^12-14. Our …

Targeting Delivery Of Bcl-2 Family Protein Inhibitor Has The Potential To Treat Cancer And Fibrosis, Mohammad Nurul Huda

Open Access Theses & Dissertations

Apoptosis is a naturally occurring cell death mechanism to remove the selective cell population. B-cell leukemia/lymphoma-2 (BCL-2) family protein plays a critical role in activating the upstream apoptosis signaling pathway, primarily the intrinsic apoptosis pathway. The BCL-2 family consists of both pro-and anti-apoptotic proteins, which are structurally and functionally similar, containing up to four BCL-2 homologies (BH) motifs (BH1-4). Defecting apoptosis along this signaling pathway can lead to various events, including malignant cell transformation, tumor metastasis, tissue fibrosis, and drug resistance. In fibrosis, the aberrant apoptosis signaling also activates multiple effector proteins and growth factors, such as TGF-β, CTGF, and …

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …

The Regulation Of Pannexin1 And Pannexin2 In The Skin In Health And Disease, Rafael E. Sanchez Pupo

Electronic Thesis and Dissertation Repository

Pannexins (PANX1, 2, 3) are a family of channel-forming glycoproteins that mediate intracellular and paracrine signaling. In contrast to PANX2, PANX1 has been extensively investigated in the skin, modulating cell differentiation, wound healing, and melanoma development. PANX1 and PANX2 can co-exist in the same cell and form mixed channels where their glycosylation seems to regulate their intermixing. N-glycosylation and caspase cleavage have been proposed as modulators of the function of PANX1, but their effects on PANX2 are unknown. We explored the PANX2 expression in mouse skin and showed that a Panx2 splice variant (PANX2-202) is continuously expressed throughout aging skin. …

A Comparative Study On Cannabidiol In Melanoma Migration And Invasion: Charlotte's Web Vs. Purified Cbd, 2020–2021, Ruby Thamert

Theses

Over the last decade, much attention has been focused on compounds from Cannabis sativa in treating a variety of diseases including cancer. This study examines the abilities of two different cannabidiol oils to decrease the migration and invasion of melanoma cells in vitro. Skin cancers are the most common cancers in the world. While malignant melanoma is the least common type of skin cancer, it is the deadliest. Patients diagnosed with stage IV disease have only a 15-20% five-year survival rate even with aggressive multimodal treatment, demonstrating the need for additional therapeutic options. Because melanoma is often fatal when …

Impact Of Intratumor Heterogeneity And The Tumor Microenvironment In Shaping Tumor Evolution And Response To Therapy, Akash Mitra

Dissertations & Theses (Open Access)

Intratumor heterogeneity (ITH) is a crucial challenge in cancer treatment. The genotypic and phenotypic heterogeneity underlying diverse cancer types leads to subclonal variation, which may result in mixed or failed response to therapy. The heterogeneity at the tumor level, along with the tumor microenvironment (TME), often shapes tumor evolution and ultimately clinical outcome. Given that modern treatment paradigms increasingly expose patients with metastatic disease to multiple treatment modalities through the course of their disease, there exists a need to characterize robust and predictive biomarkers of response to therapy. In order to accurately characterize tumor evolution, we need to account for …

Elucidating The Roles Of Il-15 In The Tumor Microenvironment, Rosa Maria Santana Carrero

Dissertations & Theses (Open Access)

ELUCIDATING THE ROLES OF IL-15 IN THE TUMOR MICROENVIRONMENT

Rosa M. Santana Carrero, B.S.

Advisory Professors: Shao-Cong Sun, Ph.D. & Kimberly S. Schluns, Ph.D.

Interleukin-15 (IL-15) is a factor that promotes activation, proliferation, cytotoxicity, and survival of CD8 T cells and NK cells, and has been shown to have anti-tumor effects. Moreover, loss of IL-15 expression in human colorectal tumors correlates with increased risk of relapse, diminished survival, decreased density and proliferation of T cells. All together these findings suggest that IL-15 expressed locally in the tumor microenvironment (TME) is an important mediator of anti-tumor responses by tumor infiltrating lymphocytes …

Il-1Α Blockade Reduces Immune Suppression In The Early Tumor Micro-Environment, Brenda Melendez

Dissertations & Theses (Open Access)

IL-1α Blockade Reduces Immune Suppression in the Early Tumor Micro-Environment

Brenda Melendez, B.S.

Advisory Professor: Gregory Lizee, PhD.

Immunotherapy against melanoma has shown great promise in the clinic for treating advanced-stage patients. However, a major barrier against effective T cell mediated cytotoxicity is immunosuppression in the tumor micro-environment. It has been described that tumors secrete pro-inflammatory cytokines capable of modulating immune responses that favors the growth of tumor cells. Specifically, IL-1 plays a critical role in myeloid cell recruitment and activation, which can in turn inhibit T cell activity in vivo. Moreover, IL-1 is also known to up-regulate immune inhibitory …

Evaluation Of Oncolytic And Immunomodulatory Potential Of The Hsv-1 Live-Attenuated Vaccine Strain Vc2 In An Immunocompetent Murine Melanoma Model, Natalie Wall Fowlkes

LSU Doctoral Dissertations

Melanoma accounts for 90% of skin cancer-related deaths in humans. Treatment options for metastatic melanoma in people is very limited. Melanoma is considered to be an immunogenic tumor, spurring interest in development of immunotherapies for the treatment of metastatic melanoma. Oncolytic virotherapy has been widely investigated. The first ever oncolytic virotherapy to receive FDA-approval is an HSV-1-based virus (Talimogene Laherperavec (T-Vec) or Imlygic) containing a transgene for human GM-CSF to enhance anti-tumor immune responses after injection. Durable response rate in human patients was only 16% despite impressive efficacy in anti-tumor effects in vitro and in murine tumor models. Novel viruses …

Integrative Cancer Immunogenomic Analysis Of Serial Melanoma Biopsies Reveals Correlates Of Response And Resistance To Sequential Ctla-4 And Pd-1 Blockade Treatment, Whijae Roh

Dissertations & Theses (Open Access)

Melanoma is the most malignant form of skin cancer. The five-year survival rate for metastatic melanoma is 19.9%. Although targeted therapy of BRAF and MEK inhibitors were developed for melanoma, resistance to therapy is inevitable. Immune checkpoint blockade, which reverses the suppression of the immune system, on the other hand, has shown a durable response in 20-30% of patients with metastatic melanoma. However, more predictive and robust biomarkers of response to this therapy are still needed, and resistance mechanisms remain incompletely understood. To address this, we examined a cohort of metastatic melanoma patients treated with sequential checkpoint blockade against cytotoxic …

Clinical And Therapeutic Significance Of Obesity In Melanoma, Jennifer L. Mcquade

Dissertations & Theses (Open Access)

While the FDA approval of targeted and immune therapies in metastatic melanoma (MM) have dramatically improved outcomes in this disease, de novo and/or acquired resistance can limit the clinical benefit of these agents. The IGF-1/PI3K/AKT pathway has been implicated in resistance to both targeted and immune therapy. The IGF-1/PI3K/AKT pathway has also been shown to play a key role in the pathogenesis of obesity in other malignancies. To date, the impact of energy balance on clinical outcomes and therapeutic response in MM has not been studied. I hypothesized that energy balance would impact the molecular biology, behavior, and drug sensitivity …

Alternative Methods For The Treatment Of Chemo-Resistant Cancers, Kaitlyn Wong

Doctoral Dissertations

Great strides have been made in cancer therapy in the past century, yet it remains one of the leading causes of death in the United States today. This work aimed to shed light on novel methods to treat a variety of aggressive and often chemo-resistant cancers both in vitro and in vivo. The first aim of this work was to evaluate the therapeutic efficacy of poly(methacryloyloxyethyl phosphorylcholine) (polyMPC) prodrugs compared to standard chemotherapeutic agents. Conjugation of polyMPC to drugs such as doxorubicin (Dox) can result in its improved solubility, prolonged half-life and therapeutic efficacy. PolyMPC and polyMPC-Dox (at a …

Selective Elimination Of Malignant Melanoma Using The Novel Anti-Tumor Agents, Osw-1 And Peitc, Kausar Begam Riaz Ahmed

Dissertations & Theses (Open Access)

Metastatic melanoma is amongst the most refractory of cancers. Drug resistance and lack of therapeutic selectivity are two main challenges to successful melanoma therapy. Herein, we investigated the mechanims of anticancer activity and therapeutic selectivity of two novel agents, 3β, 16β, 17α-trihydroxycholest-5-en-22-one 16-O-[2-O-4-methoxybenzoyl-β-D-xylopyranosyl]- [1→3]-2-O-acetyl-α-l-arabinopyranoside (OSW-1) and β-Phenylethyl Isothiocyanate (PEITC) in melanoma.

OSW-1 inhibited melanoma cell viability at nanomolar concentrations with minimal toxicity to normal melanocytes. Mechanistic studies revealed that OSW-1 suppressed Disialoganglioside 3 Synthase (GD3S) gene expression in melanoma cells, leading to inhibition of gangliosides GD3 and GD2. GD3 is an abundantly expressed melanoma …

The Association Between The Il-1 Pathway, Isaac C. Wun

Dissertations & Theses (Open Access)

Cutaneous malignant melanoma (CMM) is a potentially lethal malignancy that warrants attention and further research, as it is known to that there is an increasing rate of incidence in theUnited States, and it is also known that exposure to UV light is its most crucial risk factor, and family history of melanoma is also an important risk factor. Melanoma is an aggressive and lethal cancer in humans. There are an estimated new 132,000 melanoma cases annually worldwide, and the trend has doubled in the past 20 years. However, attempts to treat melanoma have encountered considerable resistance and remained ineffective. The …

Galectin-3 Enhances The Malignant Melanoma Phenotype By Regulating Autotaxin, Russell R. Braeuer

Dissertations & Theses (Open Access)

In melanoma patient specimens and cell lines, the over expression of galectin-3 is associated with disease progression and metastatic potential. Herein, we have sought out to determine whether galectin-3 affects the malignant melanoma phenotype by regulating downstream target genes. To that end, galectin-3 was stably silenced by utilizing the lentivirus-incorporated small hairpin RNA in two metastatic melanoma cell lines, WM2664 and A375SM, and subjected to gene expression microarray analysis. We identified and validated the lysophospholipase D enzyme, autotaxin, a promoter of migration, invasion, and tumorigenesis, to be down regulated after silencing galectin-3. Silencing galectin-3 significantly reduced the promoter activity of …

Characterization Of Differentiation And Prognostic Biomarkers On Cd8+ Tumor-Infiltrating Lymphocytes In Metastatic Melanoma, Richard C. Wu

Dissertations & Theses (Open Access)

CD8⁺ cytotoxic T lymphocytes (CTL) frequently infiltrate tumors, yet most melanoma patients fail to undergo tumor regression. We studied the differentiation of the CD8⁺ tumor-infiltrating lymphocytes (TIL) from 44 metastatic melanoma patients using known T-cell differentiation markers. We also compared CD8⁺ TIL against the T cells from matched melanoma patients’ peripheral blood. We discovered a novel subset of CD8⁺ TIL co-expressing early-differentiation markers, CD27, CD28, and a late/senescent CTL differentiation marker, CD57. This CD8⁺CD57⁺ TIL expressed a cytolytic enzyme, granzyme B (GB), yet did not express another cytolytic pore-forming molecule, perforin (Perf). In …

Histone Deacetylases As Targets For Melanoma Immunotherapy, David Michael Woods

USF Tampa Graduate Theses and Dissertations

Cancer represents the second leading cause of death in the United States. For many malignancies, currently available treatment options offer little long-lasting survival benefits to patients. However, recent studies have shown immunotherapeutic approaches to be an attractive strategy to cancer treatment. While many current immunotherapeutic strategies convey durable responses, such responses are only seen in a minority of patients. An increased understanding of the mechanisms governing tumor immunogenicity and the biology of immune responses is crucial to improving upon the efficacy of current and future cancer immunotherapies. Histone deacetylases (HDACs), enzymes classically associated with regulation of gene expression, have been …

Metastatic Disease: Interactions Between Tumor Cells And Host Environment During Cancer Cell Spread, Jennifer M. Maclean

Electronic Thesis and Dissertation Repository

Tumor and metastasis formation are not cell autonomous phenomena, but rather an evolution of disease within and responding to the host environment. Metastatic spread from a primary tumor occurs as a result of a complex interplay between tumor cells and the host, wherein tumor cells must escape the primary tumor, enter the host vasculature, travel to and arrest in a distant tissue and survive and grow in that new organ. It is known that cells that progress through these stages must both escape and exploit host systems, yet the mechanisms used are not fully understood. Therefore, the goal of this …

In Vivo Murine Melanoma Tumor Responses To Nanosecond Pulsed Electric Field Treatment, Xinhua Chen

Theses and Dissertations in Biomedical Sciences

High intensity nanosecond pulsed electric fields (nsPEF) were applied to melanoma tumors to observe functional and structural biological changes and to investigate the possible molecular mechanisms responsible. An animal model was set up by injecting B16F10 mouse melanoma cells into SKH-1 mice. A treatment (Tx) of 100 pulses: 300 nanosecond duration; 40 kV/cm field strength; at 0.5 Hz rate were delivered to melanoma tumors in 120 mice. The nsPEF Txcaused tumor self-destruction with sharply decreased cell volumes and shrunken nuclei. The apoptotic biochemical tests confirmed nsPEF Tx induced apoptosis in a time-dependent manner. Examination of gross vessel and micro-vessel density …

Nanosecond Pulsed Electric Fields Induce A Mitochondria-Independent Apoptosis In B16f10 Melanoma Cells In Vitro, Wentia Elissa Ford

Theses and Dissertations in Biomedical Sciences

Nanosecond pulsed electric fields (nsPEFs) are ultra-short pulses that induce direct electric field and biological effects that initiate apoptosis. Here the application of ten 300ns pulses ranging in electric fields from 12kV/cm-60kV/cm was administered to determine the effects on B16F10 melanoma cells evaluated by in vitro studies. Initial application of nsPEFs demonstrated apoptosis induction in an electric field- and pulse number-dependent manner measured by caspase activation that correlated with decrease in cell viability 24hr post pulse. In addition caspase activity was shown to be independent of calcium mobilization though ions may play a part in other aspects of apoptosis. The …