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Full-Text Articles in Molecular Biology

Protacs – A Novel And Rapidly Developing Field Of Targeted Protein Degradation, Hannah R. Gatley Jan 2023

Protacs – A Novel And Rapidly Developing Field Of Targeted Protein Degradation, Hannah R. Gatley

Theses and Dissertations

There is a continued need for new technology and strategies for tackling cancer and other diseases, and within the current century a novel therapeutic strategy has emerged in the realm of targeted protein degradation called Proteolysis-Targeting Chimeras (PROTACs). This technology specifically targets and degrades disease-causing proteins via the ubiquitin-proteasome system, and has seen an explosion of research and intrigue in both academia and industry over the past two decades. The diversity of PROTAC classes based on the E3 ligase recruiting ligand and the target protein allows for a universal molecular structure that can be customized for a specific target and …


Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty Jan 2023

Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty

Honors Theses and Capstones

Nearly one out of six deaths in 2020, around ten million people, were caused by cancer, making it a leading cause of death worldwide (WHO, 2022). This major public health issue, in addition to the rise of multidrug-resistant (MDR) pathogens, provides a high demand for the discovery of new pharmaceutical drugs to be used clinically to treat these conditions. The Streptomyces genus accounts to produce 39% of all microbial metabolites currently approved for human health, indicating its potential as an important species to study for antimicrobial and anticancer agents. The long linear genome of Streptomyces contains specialized sequences known as …


Differentiating The Mechanistic Role And Chemotherapeutic Potential Of Src And Podoplanin In Oncogenic Transformation, Edward P. Retzbach Dec 2021

Differentiating The Mechanistic Role And Chemotherapeutic Potential Of Src And Podoplanin In Oncogenic Transformation, Edward P. Retzbach

Graduate School of Biomedical Sciences Theses and Dissertations

There were an estimated 20 million new cancer cases worldwide in 2020, resulting in nearly 1000 deaths per hour [1]. Oral cancer exemplifies the difficulties of treating cancer patients. The first line for oral cancer treatment is surgery and radiation that can lead to patient disfigurement and decreased quality of life in cancer survivors [2-4]. Though there have been many developments in chemotherapy in the last 30 years, the 50% mortality rate associated with oral cancer has not changed [4, 5]. Longitudinal studies that track survival rates in oral cancer patients demonstrate a 3-fold reduction in patient deaths when patients …


A Time-Course Characterization Of Muscle Function And Mitochondrial Markers During Colorectal Cancer-Induced Cachexia In Tumor-Bearing Male Mice, Ana Cabrera Ayuso Jul 2021

A Time-Course Characterization Of Muscle Function And Mitochondrial Markers During Colorectal Cancer-Induced Cachexia In Tumor-Bearing Male Mice, Ana Cabrera Ayuso

Graduate Theses and Dissertations

Cachexia is a multisystemic and multifactorial syndrome prevalent in cancer patients. It is clinically defined by involuntary loss of >5% weight in a six-month window, despite nutritional interventions. A negative energy balance characterizes cancer cachexia (CC), it is associated with weakness and fatigue in skeletal muscle. Impaired muscle function is associated with lower quality of life in cancer patients. Defects in mitochondrial function are strongly associated with muscle wasting. This study explored muscular contractile function and mitochondrial quality control (MQC) markers in soleus, gastrocnemius, and tibialis anterior (TA) muscles of C26-induced male tumor-bearing mice during a 25-day time course. It …


Evolution Of Targeted Therapy Resistance In Eml4-Alk Positive Non-Small Cell Lung Cancer, Robert Vander Velde Jun 2021

Evolution Of Targeted Therapy Resistance In Eml4-Alk Positive Non-Small Cell Lung Cancer, Robert Vander Velde

USF Tampa Graduate Theses and Dissertations

Targeted therapies have emerged as potent treatments that lead to the remission of many tumors. However, they rarely cure cancers in advanced, metastatic settings. This is due to the evolution of resistance, which in turn can be ascribed to the survival of small subpopulations of tolerant and/or resistant cells. Here we investigated the evolution of resistance to EML4-ALK inhibitors in non-small cell lung cancer (NSCLC) and demonstrated that resistance evolves gradually, from unique pre-treatment sub-populations, as multiple resistance mechanisms accumulate in a Darwinian fashion. Despite accumulating multiple changes, cells evolved, in parallel, toward similar inhibitor specific phenotypes. Evolving cells have …


Understanding The Role Of Ano1 In Oral Cancer, Mallary Forrest May 2021

Understanding The Role Of Ano1 In Oral Cancer, Mallary Forrest

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2008, the gene ANO1 was discovered to encode a calcium activated chloride channel. This gene is located on the 11q13 locus, a locus that is commonly amplified in many cancers including cancer of the head and neck. ANO1 is situated in close proximity to genes associated with growth and apoptosis. As rapid proliferation and lack of apoptosis are hallmark characteristics of cancer, growth factors and apoptosis mediators are expected to be altered in cancer. But what does a calcium activated chloride channel have to contribute to cancer’s pathogenesis? Is it an active gene in cancer progression or is it …


Biophysical Characterization Of The Par-4 Tumor Suppressor: Evidence Of Structure Outside The Coiled Coil Domain And Interactions With Platinum Chemotherapeutics, Andrea Megan Clark Apr 2021

Biophysical Characterization Of The Par-4 Tumor Suppressor: Evidence Of Structure Outside The Coiled Coil Domain And Interactions With Platinum Chemotherapeutics, Andrea Megan Clark

Chemistry & Biochemistry Theses & Dissertations

Prostate apoptosis response-4 (Par-4) is an apoptosis-inducing tumor suppressor protein. Full-length Par-4 has previously been shown to be a predominantly intrinsically disordered protein (IDP) under neutral conditions, with significant regular secondary structure evident only within the C-terminal coiled coil domain. However, IDPs can gain ordered structure through the process of induced folding, which often occurs under non-neutral conditions. Previous work has shown that the Par-4 leucine zipper, which is a subset of the C-terminal coiled coil domain, is disordered under neutral conditions, but forms a dimeric coiled coil at acidic pH. Increase in ionic strength was also shown to increase …


Mechanisms Of Cross-Presentation By Cdc1s, Derek James Theisen Aug 2020

Mechanisms Of Cross-Presentation By Cdc1s, Derek James Theisen

Arts & Sciences Electronic Theses and Dissertations

Classical dendritic cells (cDCs) are specialized antigen presenting cells that can be divided into distinct subsets based on the types of pathogens they respond to and the type of immune response they generate. The cDC1 subset is specialized in priming CD8 T cell responses through the process of cross-presentation. During cross-presentation, exogenous protein antigens are taken up by cDC1 and presented on MHCI molecules, allowing for the priming of CD8 T cells during conditions when DCs themselves are not directly infected. The ability to cross-present in vivo is unique to cDC1, and is essential for anti-viral responses and rejection of …


Exosomes And Their Role In Asbestos Exposure And Mesothelioma, Phillip Blake Munson Jan 2019

Exosomes And Their Role In Asbestos Exposure And Mesothelioma, Phillip Blake Munson

Graduate College Dissertations and Theses

Malignant mesothelioma (MM) is a locally invasive and highly aggressive cancer arising on the mesothelial surface of organ cavities (mainly pleural) as a direct result of asbestos exposure. The latency period of MM is long (20-50yrs) after initial asbestos exposure, and the prognostic outcomes are dismal with median life expectancy of 6-12 months post-diagnosis. There are no useful biomarkers for early MM diagnosis, no successful therapeutic interventions. These vast voids of knowledge led to our hypotheses that secreted vesicles, termed exosomes, play an important role in MM development and tumorigenic properties. Exosomes are nano-sized particles secreted from all cell types …


The Regulation Of Dna Methylation In Mammalian Development And Cancer, Nicolas Veland May 2018

The Regulation Of Dna Methylation In Mammalian Development And Cancer, Nicolas Veland

Dissertations & Theses (Open Access)

DNA methylation is an essential epigenetic modification in mammals, as it plays important regulatory roles in multiple biological processes, such as gene transcription, maintenance of chromosomal structure and genomic stability, genomic imprinting, retrotransposon silencing, and X-chromosome inactivation. Dysregulation of DNA methylation is associated with various human diseases. For example, cancer cells usually show global hypomethylation and regional hypermenthylation, which have been implicated in genomic instability and tumor suppressor silencing, respectively. Although great progress has been made in elucidating the biological functions of DNA methylation over the last several decades, how DNA methylation patterns and levels are regulated and dysregulated is …


Studies Of Norspermidine Uptake In Drosophila Suggest The Existence Of Multiple Polyamine Transport Pathways, Michael Dieffenbach Jan 2018

Studies Of Norspermidine Uptake In Drosophila Suggest The Existence Of Multiple Polyamine Transport Pathways, Michael Dieffenbach

Honors Undergraduate Theses

Polyamines are a class of essential nutrients involved in many basic cellular processes such as gene expression, cell proliferation, and apoptosis. Without polyamines, cell growth is delayed or halted. Cancerous cells require an abundance of polyamines through a combination of synthesis and transport from the extracellular environment. An FDA-approved drug, D,L-α-difluoromethylornithine (DFMO), blocks polyamine synthesis but is ineffective at inhibiting cell growth due to polyamine transport. Thus, there is a need to develop drugs that inhibit polyamine transport to use in combination with DFMO. Surprisingly, little is known about the polyamine transport system in humans and other eukaryotes. Understanding the …


B7h6: A Cancer Biomarker For The Development Of Novel Immunotherapy Approaches, Mariana Phillips May 2017

B7h6: A Cancer Biomarker For The Development Of Novel Immunotherapy Approaches, Mariana Phillips

Seton Hall University Dissertations and Theses (ETDs)

Cancer-based immunotherapy has led the evolution of biologics that can stimulate immune responses towards tumor eradication. The synthesis of small to intermediate size molecules with the targeting and effector functions of mAb may represent a novel class of immunotherapeutics that may overcome the limitations of their biological counterparts.Towards this objective, B7H6 has been identified as a protein ligand localized on the cell surface of transformed tumor cells. B7H6 binds specifically to the activating receptor NKp30, constitutively expressed on all resting and active NK cells. Upon ligand:receptor binding, B7H6 triggers NK cell activation and release of chemokines and pro-inflammatory cytokines such …


Investigating E2f Independent Cell Cycle Control And Tumor Suppression By Prb, Michael J. Thwaites Apr 2017

Investigating E2f Independent Cell Cycle Control And Tumor Suppression By Prb, Michael J. Thwaites

Electronic Thesis and Dissertation Repository

Cellular division is primarily controlled at the G1 to S-phase transition of the cell cycle by the retinoblastoma tumor-suppressor protein (pRB). The ability of pRB to restrict S-phase entry is primarily attributed to the repression of E2F transcription factors required to upregulate cell cycle target genes necessary for cellular division. Interestingly, while pRB is disrupted in the vast majority of human cancers, mutations typically target upstream regulators of pRB leading to inactivation through hyperphosphorylation. The rarity of direct pRB mutations suggests that the regulation of the cell cycle by pRB may involve additional mechanisms outside of E2F repression, as this …


Characterization Of Staphylococcal Nuclease And Tudor Domain Containing Protein 1 (Snd1) As A Molecular Target In Hepatocellular Carcinoma And Non-Alcoholic Steatohepatitis, Nidhi H. Jariwala Jan 2017

Characterization Of Staphylococcal Nuclease And Tudor Domain Containing Protein 1 (Snd1) As A Molecular Target In Hepatocellular Carcinoma And Non-Alcoholic Steatohepatitis, Nidhi H. Jariwala

Theses and Dissertations

CHARACTERIZATION OF STAPHYLOCOCCAL NUCLEASE AND TUDOR DOMAIN CONTAINING PROTEIN 1 (SND1) AS A MOLECULAR TARGET IN HEPATOCELLULAR CARCINOMA AND NON-ALCOHOLIC STEATOHEPATITIS

Nidhi Jariwala, PhD

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Integrative Life Sciences

Virginia Commonwealth University, 2017

Devanand Sarkar, M.B.B.S., PhD.

Associate Professor, Department of Human and Molecular Genetics

Virginia Commonwealth University

Richmond, Virginia

SND1, a subunit of the miRNA regulatory complex RISC, has been implicated as an oncogene in hepatocellular carcinoma (HCC). Oncoprotein SND1 regulates gene expression at a post-transcriptional level in multiple cancers including hepatocellular carcinoma (HCC). …


Investigating The Roles Of Δnp63 As A Suppressor Of Migration, Invasion, And Metastasis, Ramon E. Flores Gonzalez Aug 2016

Investigating The Roles Of Δnp63 As A Suppressor Of Migration, Invasion, And Metastasis, Ramon E. Flores Gonzalez

Dissertations & Theses (Open Access)

Cancer is one of the leading causes of death and disease in the world. Considerable resources are spent to study and understand cancer, with the hope of developing new treatments and eventually cures that will help millions of people. Efforts to understand cancer are hindered by its inherent complexity and instability. Nonetheless, understanding the basics of tumor development and progression are the key to focused on studying the role of ΔNp63 in cancer, a p53 family member known to be involved in epithelial development, microRNA biogenesis, and stem cell maintenance. Using the strength of in vivo mouse models, we found …


Cell Cycle Arrest By Tgfß1 Is Dependent On The Inhibition Of Cmg Helicase Assembly And Activation, Brook Samuel Nepon-Sixt Jun 2016

Cell Cycle Arrest By Tgfß1 Is Dependent On The Inhibition Of Cmg Helicase Assembly And Activation, Brook Samuel Nepon-Sixt

USF Tampa Graduate Theses and Dissertations

Tumorigenesis is a multifaceted set of events consisting of the deregulation of several cell-autonomous and tissue microenvironmental processes that ultimately leads to the acquisition of malignant disease. Transforming growth factor beta (TGFß) and its family members are regulatory cytokines that function to ensure proper organismal development and the maintenance of homeostasis by controlling cellular differentiation, proliferation, adhesion, and survival, as well as by modulating components of the cellular microenvironment and immune system. The pleiotropic control by TGFß of these cell intrinsic and extrinsic factors is intimately linked to the prevention of tumor formation, the specifics of which are dependent on …


Immune Modulating Functions By Soypeptide Lunasin In Cancer Immunotherapy, Chun-Yu Tung May 2016

Immune Modulating Functions By Soypeptide Lunasin In Cancer Immunotherapy, Chun-Yu Tung

Open Access Dissertations

Chemotherapy is currently the mainstay of treatment for most cancer patients. Despite its efficacy in eliminating cancer cells, a high percentage of chemotherapy patients eventually relapse or suffer progression of the disease. Immunosurveillance is capable of recognizing and eliminating continuously arising transformed mutant cells, and thus cancer immunotherapy is one of the emerging therapeutic strategies that harnesses the power of the immune system to eradicate chemotherapy-resistant cancerous cells. However, the adverse side effects of chemotherapy impede the therapeutic effects of immunotherapy. Our previous studies demonstrate that lymphoma patients are refractory to clinical immunotherapy because of chemotherapy-induced immune dysfunction. In addition, …


Alternative Regulation Of Myc In Lung Cancer, Patrick N. Backman Mar 2016

Alternative Regulation Of Myc In Lung Cancer, Patrick N. Backman

Open Access Theses

Lung cancer is the leading cause of cancer deaths in the United States, accounting for 27% of all cancer induced deaths1. In an attempt to create a effective targeted therapy for the treatment of lung cancer, a strategy used to treat an activated KrasG12D/+;p53 R172H/+ transgenic lung cancer mouse model was to deliver a known tumor suppressive microRNA (miRNA) to stop tumor growth. The tumor suppressive miRNA let-7 was lentivirally delivered in the form of its primary transcript, pri-let-7a-1, and resulted in increased lung size and inflammation compared to lungs exposed to a control lentivirus. It was identified …


A Requirement For Y841 In Jak3 Enzymatic Activity And Hematopoietic Cancers, George Steven Martinez Jan 2016

A Requirement For Y841 In Jak3 Enzymatic Activity And Hematopoietic Cancers, George Steven Martinez

Open Access Theses & Dissertations

A medical need exists for successfully treating people afflicted with leukemia, especially those who develop drug resistant forms. Relapse leukemia cases are particularly high within Hispanic populations where this disease is among the most frequently occurring cancer. Fourteen somatic mutations have been reported in Janus tyrosine kinase 3 (Jak3), including M511I and A573V, from patients with various forms of leukemia. To monitor drug sensitivity, a model system was developed. Indeed, many of these mutations have been shown to possess transforming ability in cell lines such as the IL-3 dependent pro-B cell line Ba/F3. As such, Ba/F3 cells were transformed to …


Interaction Between Atm Kinase And P53 In Determining Glioma Radiosensitivity, Syed F. Ahmad Jan 2015

Interaction Between Atm Kinase And P53 In Determining Glioma Radiosensitivity, Syed F. Ahmad

Theses and Dissertations

Glioblastoma multiforme (GBM) is the most common primary brain tumor. Studies have shown that targeting the DNA damage response can sensitize cancer cells to DNA damaging agents. Ataxia telangiectasia mutated (ATM) is involved in signaling DNA double strand breaks. Our group has previously shown that ATM inhibitors (ATMi) sensitize GBM cells and tumors to ionizing radiation. This effect is greater when the tumor suppressor p53 is mutated.

The goals of this work include validation of a new ATM inhibitor, AZ32, and elucidation of how ATMi and p53 status interact to promote cell death after radiation. We propose that ATMi and …


Rna Aptamers For Molecular Chaperones Hsp27 And Hsp90, Sathishkumar Kumar Munusamy Jan 2015

Rna Aptamers For Molecular Chaperones Hsp27 And Hsp90, Sathishkumar Kumar Munusamy

Legacy Theses & Dissertations (2009 - 2024)

Hsp90 and Hsp27 are members of the heat shock protein family of chaperones that perform multiple roles in cellular maintenance through protein folding and inhibition of apoptosis. They are abundantly expressed in cells and are over-expressed during conditions of stress. Hsp90 requires ATP for its chaperone function while Hsp27 self-associates into higher order oligomers enclosing its substrate. Their ability to interact with other proteins or with themselves lies at the heart of their mechanisms. The specific consequences of each of their interactions on global cellular health have not yet been fully discovered. The sheer diversity of proteins that interact with …


Molecular Studies On The Anti-Tumor Effects Of Metal-Based Complexes: Involvement Of The Ubiquitin-Proteasome And Apoptotic Pathways, Sara M. Schmitt Jan 2014

Molecular Studies On The Anti-Tumor Effects Of Metal-Based Complexes: Involvement Of The Ubiquitin-Proteasome And Apoptotic Pathways, Sara M. Schmitt

Wayne State University Dissertations

The ubiquitin-proteasome pathway is crucial to normal cellular function, and as such, has been extensively investigated as a potential target for cancer therapeutics. Many compounds have been tested for their proteasome inhibitory ability, including various small peptide aldehydes, and, following the success of cisplatin, several metal-containing complexes. The efficacy of these compounds in preclinical studies ultimately resulted in the development and approval of the first-in-class proteasome inhibitor bortezomib, the use of which, unfortunately, has been hindered by toxicity and resistance. These limitations have led to a massive push toward designing and developing new, less toxic proteasome inhibitors for clinical use. …


A Study On The Function Of 14-3-3sigma In Regulating Cancer Energy Metabolism, Liem M. Phan, Liem M. Phan Dec 2012

A Study On The Function Of 14-3-3sigma In Regulating Cancer Energy Metabolism, Liem M. Phan, Liem M. Phan

Dissertations & Theses (Open Access)

Metabolic reprogramming has been shown to be a major cancer hallmark providing tumor cells with significant advantages for survival, proliferation, growth, metastasis and resistance against anti-cancer therapies. Glycolysis, glutaminolysis and mitochondrial biogenesis are among the most essential cancer metabolic alterations because these pathways provide cancer cells with not only energy but also crucial metabolites to support large-scale biosynthesis, rapid proliferation and tumorigenesis. In this study, we find that 14-3-3σ suppresses all these three metabolic processes by promoting the degradation of their main driver, c-Myc. In fact, 14-3-3s significantly enhances c-Myc poly-ubiquitination and subsequent degradation, reduces c-Myc transcriptional activity, and down-regulates …


Matrix Metalloproteinase Genes Are Transcriptionally Regulated By E2f Transcription Factors: A Link Between Cell Cycle Control And Metastatic Progression, Jacqueline Lea Johnson Feb 2012

Matrix Metalloproteinase Genes Are Transcriptionally Regulated By E2f Transcription Factors: A Link Between Cell Cycle Control And Metastatic Progression, Jacqueline Lea Johnson

USF Tampa Graduate Theses and Dissertations

The RbµE2F transcriptional regulatory pathway plays a critical role in the cell cycle. Rb is inactivated through multiple waves of phosphorylation, mediated mainly by cyclin D and cyclin E associated kinases. Once Rb is inactivated, cells can enter Sµphase. Collectively, three Rb family members and ten E2F proteins coordinate every additional stage of the cell cycle, from quiescence to mitosis. However the RbµE2F pathway is frequently altered in cancer. Aside from cell proliferation, the RbµE2F pathway regulates other essential cellular processes including apoptosis, cell differentiation, angiogenesis and DNA damage repair pathways, but its role in invasion and cancer progression is …


Modulation Of Anti-Tumor Immune Response By Tgf-Β-Inducible Early Gene 1 (Tieg1), Andi Cani Jan 2012

Modulation Of Anti-Tumor Immune Response By Tgf-Β-Inducible Early Gene 1 (Tieg1), Andi Cani

Wayne State University Theses

Cancer immunotherapy has had limited clinical efficacy partly because regulatory T cells (Treg) suppress the immune response to tumor-associated antigens. Inducible regulatory T cells (iTreg), which are converted from naïve CD4 T cells by TGF-β, an abundant cytokine in the tumor microenvironment, may contribute to this immune suppression. Induction of Foxp3 by TGF-β is mediated by the transcription factor TIEG1 and abrogation of this protein prevents Foxp3 expression. We are testing the hypothesis that blockade of TIEG1 to prevent iTreg conversion will enhance immune response in DNA vaccination to the tumor associated antigen Her-2. Wild type and TIEG1 knockout mice …


Hedgehog Signaling: A Potential Therapeutic Target For Non-Small Cell Lung Cancer, Ma'in Yehya Maitah Jan 2011

Hedgehog Signaling: A Potential Therapeutic Target For Non-Small Cell Lung Cancer, Ma'in Yehya Maitah

Wayne State University Dissertations

The American Cancer Society estimated that 222,520 Americans were diagnosed with lung cancer and 157,300 died of lung cancer in 2010 (Jemal et al. 2009, 225-249;Jemal et al. 2011, 69-90). The clinical outcome of patients diagnosed with non-small cell lung cancer (NSCLC), the major lung cancer sub-types, is very poor, which calls for innovative research for finding novel therapeutic targets and agents for better treatment outcome.

Emerging evidences have suggested that a phenomenon called Epithelial-to-Mesenchymal Transition (EMT), which shares similar molecular characteristics with cancer stem-like cells, contributes to lung cancer treatment failure. In view of the fact that EMT process …


The Cellular And Molecular Dynamics Of The Queuosine Modification In Transfer Rna: Definition, Modulation, Deficiencies And Effect Of The Queuosine Modification System, Rana C. Morris Jul 1997

The Cellular And Molecular Dynamics Of The Queuosine Modification In Transfer Rna: Definition, Modulation, Deficiencies And Effect Of The Queuosine Modification System, Rana C. Morris

Theses and Dissertations in Biomedical Sciences

The presence of the queuosine modification in the wobble position of tRNAasn, tRNasp, tRNAhis, and tRNAtyr is associated with a decrease in cellular growth rate, an increase in the ability to withstand environmental stress, and differentiation of pleuripotent cells into mature phenotypes. The loss of this normal modification is strongly correlated with neoplastic transformation and tumor progression of a wide variety of cancers.

The "normal" system for formation of the queuosine modification in tRNA was studied in human fibroblast cell cultures and in mouse, rat and human liver tissues. The queuosine modification system …