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A Noncanonical Function Of The Telomerase Rna Component In Human Embryonic Stem Cells, Kirsten Ann Brenner

Arts & Sciences Electronic Theses and Dissertations

Telomeres are stretches of TTAGGG nucleotide repeats located at the ends of linear chromosomes that shorten with progressive cell division and prevent genomic instability at the cost of limiting a cell’s capacity to proliferate. This limitation can be overcome by telomerase, a ribonucleoprotein complex that elongates telomeres via reverse-transcription of the template telomerase RNA component (TERC). Recent studies have reported potential functions of TERC outside of its role in telomere maintenance. These noncanonical functions of TERC are however poorly defined, and the molecular mechanisms and biological relevance behind such functions remain elusive. Here, we generated conditional TERC knock-out human embryonic …

Exploration Of Ataxia Telangiectasia And Rad3-Related’S (Atr’S) Role In Cell Death Regulation: Implications In Development, Cancer, And Stroke, Brian Cartwright

Electronic Theses and Dissertations

From gametogenesis until death an organism’s genome is under constant bombardment from endogenous and exogenous sources of DNA damage. To maintain genomic integrity amid this damage, cells have evolved responses which allow them to either preserve viability for recovery or initiate self-destructive pathways depending on the severity of DNA damage. One protein involved in initiating and carrying out these responses is the protein kinase ataxia telangiectasia and Rad3-related (ATR). ATR is known primarily for its regulatory role in initiating the checkpoint-signaling cascade following DNA damage and replicative stress. These signaling events lead to cell cycle arrest, DNA repair, or apoptosis …

Hei-Oc1 Cochlear Cells As An In Vitro Model To Study The Role Of Connexins In Ototoxicity And Hearing Loss, Rianne Beach

Electronic Thesis and Dissertation Repository

Connexin 26 (Cx26) and Cx30 mediate the intercellular exchange of metabolites and ions within the cochlea in a process known as gap junctional intercellular communication (GJIC). Cochlear cell death and subsequent hearing loss can arise after treatment with ototoxic therapeutics and Cx26 mutant expression. We investigated the role of connexins and GJIC in the development of ototoxicity in HEI-OC1 cochlear-derived cells. The susceptibility of HEI-OC1 cells to aminoglycoside antibiotics and cisplatin-induced cell death was not influenced by the ablation of connexins and GJIC. However, the expression of mitochondrial apoptosis or ER stress markers was altered by the degree of GJIC. …

Epigenetic Reprogramming, Apoptosis, And Developmental Competence In Cloned Embryos, Laura A. Moley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cloning through somatic cell nuclear transfer (SCNT) remains highly inefficient twenty years after the first demonstration of the technology with the birth of Dolly. By increasing efficiency by selecting the embryos early in development that are most likely to succeed following transfer into a surrogate mother, the technology could be more routinely utilized to enhance animal agriculture production. SCNT is believed to be highly inefficient as a result of incorrect DNA methylation and gene expression that are accumulated because of the SCNT technique. We proposed the use of a non-toxic, non-invasive detector of cell death, to quantitatively assess embryo competency …

Analyzing The Effect Of Apoptotic Mutations On The State Of The Nascent-Polypeptide Associated Complex In Caenorhabditis Elegans, Monica Gerber

Senior Honors Projects, 2010-2019

Cells experiencing misfolded protein stress can become debilitated and die, contributing to the onset of disease. The nascent polypeptide-associated complex (NAC) is a heterodimeric translational chaperone that protects against misfolded protein stress by mediating proper protein folding and localization during translation. Depletion of this complex results in misfolded protein accumulation in the endoplasmic reticulum (ER). To determine the importance of the NAC to proteostasis, we have previously depleted the complex in C.elegans via RNA interference and observed numerous dose-dependent effects, including apoptosis of neuronal cells and changes in gene expression of hypodermal cells. While we have observed these cell-specific responses …

Telomeric Dna Damage And Repair Machineries In Hiv Infection, Lam Nguyen

Electronic Theses and Dissertations

In this thesis, we investigated T cell homeostasis and DNA damage repair machineries in HIV infection. We found that the frequencies of CD4T cells were low, which is associated with cell apoptosis in HIV patients compared to healthy subjects. Importantly, these events were closely correlated to the increase in T cell exhaustion, senescence, DNA damage, and telomere attrition. Mechanistically, while the DNA damage sensors Mer11, Rad50, and NBS1 (MRN) complexes remained intact, the ataxia-telangiectasia mutated (ATM) kinase and its downstream checkpoint kinase 2 (CHK2) were significantly inhibited during HIV infection. Additionally, telomeric repeat-binding factor 2 (TRF2) that functions to protect …

Effects Of Global Warming On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In The American Oyster, Sarah B. Nash

Theses and Dissertations

Global warming due to climate change is predicted to intensify the heat stress in marine and coastal organisms, affecting their development, growth and reproductive functions. In this study. I analyzed gonadal development, heat shock protein 70 (HSP70), nitrotyrosine protein (NTP), dinitrophenyl (DNP) expressions, cellular apoptosis, and coelomic fluid (CF) conditions in American oyster. Oysters were placed in six aquariums and exposed to control (24°C), medium (28°C), and high (32°C) temperatures for one week. Higher temperature significantly decreased the number of eggs and sperm. CF protein concentrations also declined compared to control. In contrast, CF pH and HSP70 expression in gonad …

High Molecular-Weight Hyaluronan Prevents Basal Cell Carcinoma Via Promoting Apoptosis In Cancer-Initiating Adult Stem Cells, Violet Liu

Electronic Thesis and Dissertation Repository

Basal cell carcinoma (BCC), a keratinocyte cancer, is the most common human neoplasm worldwide. Although rarely metastatic, BCC is associated with high morbidity rates with globally rising incidence rates. Accompanying the increase in newly diagnosed cases, the societal cost for BCC treatment in Canada is also expected to inflate, exceeding over $900 million/year by 2031. Chronic UVB exposure has been identified as the primary carcinogen that causes activating mutations in the hedgehog signaling pathway. However, there are no effective preventative methods against BCC, since meta-analyses report sunscreen application does not reduce BCC in compliant patients. The native high molecular-weight hyaluronan …

Mechanisms Of Oriented Cell Division And Their Roles In Tissue Development, Evan Blake Dewey

Biology ETDs

Properly executed cell division is crucial to development, maintenance, and longevity of multicellular organisms. Defects in both symmetric and asymmetric divisions can lead to improper developmental patterning, as well as genomic instability, disruption of tissue homeostasis, and cancer. Our research focuses on how regulators orchestrate proper cell divisions. Mushroom Body Defect (Mud) is one such regulator, and here we describe how Mud is regulated via the Hippo signaling pathway kinase Warts (Wts), showing Wts phosphorylates Mud to enhance interaction with the polarity protein Partner of Inscuteable, promoting spindle orientation activity. We next focus on another regulator, Shortstop (Shot), describing a …

Small Molecule Kras Agonist For Mutant Kras Cancer Therapy., Ke Xu, Dongkyoo Park, Andrew T Magis, Jun Zhang, Wei Zhou, Gabriel L Sica, Suresh S Ramalingam, Walter J Curran, Xingming Deng

Articles, Abstracts, and Reports

BACKGROUND: Lung cancer patients with KRAS mutation(s) have a poor prognosis due in part to the development of resistance to currently available therapeutic interventions. Development of a new class of anticancer agents that directly targets KRAS may provide a more attractive option for the treatment of KRAS-mutant lung cancer.

RESULTS: Here we identified a small molecule KRAS agonist, KRA-533, that binds the GTP/GDP-binding pocket of KRAS. In vitro GDP/GTP exchange assay reveals that KRA-533 activates KRAS by preventing the cleavage of GTP into GDP, leading to the accumulation of GTP-KRAS, an active form of KRAS. Treatment of human lung cancer …

Evaluating The Therapeutic Potential Of Crocin Against Diethylnitrosamine Induced Experimental Hepatocellular Carcinoma In Rats, Basma Ali Mustafa Awad

Theses

Hepatocellular carcinoma (HCC) is the fifth most common type of cancer and the third cause of cancer-related death worldwide. Liver cancer is the result of repeated injuries to the liver triggered by different causes. Currently, sorafenib is the only drug U.S. Food and Drug Administration approved targeted therapy. Sorafenib, an oral multikinase inhibitor, which inhibits the proliferation of tumor cells and blocks angiogenesis. Sorafenib has been shown to treat early and mild HCC lesions and it helped increase the survival rates at one year, but for only 44% of patients. Chemotherapies are an important line of defense when it comes …

Deciphering The Molecular Mechanism Through Which Rhus Coriaria Exerts Its Anti-Cancer Activity, Khawlah Najib Saeed Athamneh

Dissertations

Cancer remains a major health problem around the globe. Among various types of treatments, plants have been shown to have great capacity in cancer treatment, one of which is Rhus coriaria. Commonly known as sumac, Rhus coriaria is a culinary herb that is known to possess different therapeutic values including anti-oxidant and anti-microbial activities.

In this Ph.D. project, we tested the effect of Rhus coriaria extract (RCE) on the migration, invasion, and metastasis of MDA-MB-231 human breast cancer cells. We showed that non-cytotoxic concentrations of RCE inhibited migration and invasion, blocked adhesion to fibronectin, and downregulated MMP-9. Additionally, we found …

Probing Apoptotic Caspase Allostery And Exosite Interactions For Alternative Regulation, Derek J. Macpherson

Doctoral Dissertations

Programmed cell death, or apoptosis is a critical homeostatic pathway that monitors the balance of cell life and death. Apoptosis is regulated by a class of enzymes known as the cysteine aspartic proteases, or the caspases. The 12 human caspases that play important roles in the progression and regulation of apoptosis and inflammation. Caspases are tightly regulated by numerous factors including enzymatic activation, post-translational modifications, metal ligand binding, and protein modulation. Aberrant caspase activation and regulation has been implicated in the progression of numerous diseases such as proliferative diseases and neurodegeneration. The deeply entwined nature of caspases and apoptosis makes …

Induction Of Ampk Activation By N,N'-Diarylurea Fnd-4b Decreases Growth And Increases Apoptosis In Triple Negative And Estrogen-Receptor Positive Breast Cancers, Jeremy Johnson, Piotr G. Rychahou, Vitaliy M. Sviripa, Heidi L. Weiss, Chunming Liu, David S. Watt, B. Mark Evers

Markey Cancer Center Faculty Publications

Purpose

Triple negative breast cancer (TNBC) is the most lethal and aggressive subtype of breast cancer. AMP-activated protein kinase (AMPK) is a major energy regulator that suppresses tumor growth, and 1-(3-chloro-4-((trifluoromethyl)thio)phenyl)-3-(4-(trifluoromethoxy)phenyl)urea (FND-4b) is a novel AMPK activator that inhibits growth and induces apoptosis in colon cancer. The purpose of this project was to test the effects of FND-4b on AMPK activation, proliferation, and apoptosis in breast cancer with a particular emphasis on TNBC.

Materials and methods

(i) Estrogen-receptor positive breast cancer (ER+BC; MCF-7, and T-47D), TNBC (MDA-MB-231 and HCC-1806), and breast cancer stem cells were treated with FND-4b for 24h. …

Autophagic Flux Modulation By Wnt/Β-Catenin Pathway Inhibition In Hepatocellular Carcinoma, Lilia Turcios, Heather E. Chacon, Catherine Garcia, Pedro Eman, Virgilius Cornea, Jieyun Jiang, Brett T. Spear, Chunming Liu, David S. Watt, Francesc Marti, Roberto Gedaly

Surgery Faculty Publications

Autophagy targets cellular components for lysosomal-dependent degradation in which the products of degradation may be recycled for protein synthesis and utilized for energy production. Autophagy also plays a critical role in cell homeostasis and the regulation of many physiological and pathological processes and prompts this investigation of new agents to effect abnormal autophagy in hepatocellular carcinoma (HCC). 2,5-Dichloro-N-(2-methyl-4-nitrophenyl) benzenesulfonamide (FH535) is a synthetic inhibitor of the Wnt/β-catenin pathway that exhibits anti-proliferative and anti-angiogenic effects on different types of cancer cells. The combination of FH535 with sorafenib promotes a synergistic inhibition of HCC and liver cancer stem cell proliferation, …

Efficacy Of Taurine Against Aluminum Maltolate-Induced Apoptosis In Sh-Sy5y Cells Via Reduction Of Oxidative Stress, Endoplasmic Reticulum Stress, And Mitochondrial Dysfunction, Bi-Yu Liu, Yuh-Ju Lee, Hsian-Chin Jen, Deng-Fwu Hwang

Journal of Marine Science and Technology

Aluminum (Al) is one of the most abundant elements on the earth’s crust and is used in various industrial applications. However, Al is known to be associated with various neurodegenerative diseases. Taurine is a free amino acid presents at high concentrations in the brain and is crucial for neuron development. Here, the protective effects of taurine against Al-induced neurotoxicity were investigated. Al, at a concentration of 600 M, induced apoptosis of and cell cycle arrest in human neuroblastoma SH-SY5Y cells. Additionally, Al induced a 55% increase in the levels of reactive oxygen species and inhibited mitochondrial membrane potential up to …

A H2ax–Carp-1 Interaction Regulates Apoptosis Signaling Following Dna Damage, Sreeja C. Sekhar, Jaganathan Venkatesh, Vino T. Cheriyan, Magesh Muthu, Edi Levi, Hadeel Assad, Paul Meister, Vishnu V. Undyala, James W. Gauld, Arun K. Rishi

Chemistry and Biochemistry Publications

Cell Cycle and Apoptosis Regulatory Protein (CARP-1/CCAR1) is a peri-nuclear phosphoprotein that regulates apoptosis via chemotherapeutic Adriamycin (doxorubicin) and a novel class of CARP-1 functional mimetic (CFM) compounds. Although Adriamycin causes DNA damage, data from Comet assays revealed that CFM-4.16 also induced DNA damage. Phosphorylation of histone 2AX (γH2AX) protein is involved in regulating DNA damage repair and apoptosis signaling. Adriamycin or CFM-4.16 treatments inhibited cell growth and caused elevated CARP-1 and γH2AX in human breast (HBC) and cervical cancer (HeLa) cells. In fact, a robust nuclear or peri-nuclear co-localization of CARP-1 and γH2AX occurred in cells undergoing apoptosis. Knock-down …

Maternal Choline Supplementation Modulates Placental Markers Of Inflammation, Angiogenesis, And Apoptosis In A Mouse Model Of Placental Insufficiency, Julia H. King, Sze Ting (Cecilia) Kwan, Jian Yan, Xinyin Jiang, Vladislav G. Fomin, Samantha P. Levine, Emily Wei, Mark S. Roberson, Marie A. Caudill

Publications and Research

Dlx3 (distal-less homeobox 3) haploinsufficiency in mice has been shown to result in restricted fetal growth and placental defects. We previously showed that maternal choline supplementation (4X versus 1X choline) in the Dlx3+/�� mouse increased fetal and placental growth in mid-gestation. The current study sought to test the hypothesis that prenatal choline would modulate indicators of placenta function and development. Pregnant Dlx3+/�� mice consuming 1X (control), 2X, or 4X choline from conception were sacrificed at embryonic (E) days E10.5, E12.5, E15.5, and E18.5, and placentas and embryos were harvested. Data were analyzed separately for each gestational day controlling for litter …

An In Vitro And In Vivo Evaluation Of The Anticancer Potential Of Resveratrol And Pterostilbene Against Hpv-E6 Positive Cancers, Kaushiki Chatterjee

Dissertations, Theses, and Capstone Projects

Cervical cancer remains as one of the most prevalent cancers effecting women globally. Lack of awareness and affordable prophylactic and therapeutic options in developing countries drive the need for alternative low-cost approaches. Dietary polyphenols have gained increased attention as possible anti-cancer agents. Our study aims to investigate whether two natural structural analogs, resveratrol and pterostilbene, exhibit anti-HPV (Human papillomavirus) activity in cervical cancer. To determine the efficacy of these polyphenols, extensive in vitro and in vivo analyses were carried out. For the in vitro studies we utilized human HeLa cells (HPV18 positive) and murine TC1 cells (HPV 16 oncogene positive). …

Arachidin-1 And Arachidin-3 Modulation Of Rotavirus-Infected Ma104 Cells, Caleb M. Witcher, Rebekah Napier-Jameson, Hannah N. Lockwood, Macie N. Mattila, Stormey B. Wisdom, Luanna L. Saade Ferreira, Josephine Taylor, Beatrice Clack, Fabricio Medina-Bolivar, Judith M. Ball, Rebecca D. Parr

Faculty Publications

Rotavirus (RV) causes severe life-threatening diarrhea in young children and immunocompromised individuals. There are several licensed attenuated vaccines for young children, but there are no vaccines or antiviral therapeutics for immunocompromised patients of any age. Previously, our laboratory demonstrated that arachidin 1 (A1) and arachidin 3 (A3) decreases the number of infectious simian RV particles and RV non-structural protein 4 (NSP4) in a human intestinal cell line which suggests effects on RV replication. This study examined the effects of the arachidins on the human RV (Wa)-infected African green monkey kidney cell line, MA104. The addition of either A1 or A3 …

The Role Of The Cell-Surface Protease Tmprss13 In Colorectal Cancer, Fausto Alexander Varela

Wayne State University Dissertations

Colorectal cancer (CRC) is one of the most common and deadly cancers in both men and women in the United States. Extracellular proteolysis is often dysregulated in cancer including (CRC), resulting in degradation of extracellular matrix, as well as cleavage, processing, or shedding of cell adhesion molecules, growth factors, and cytokines. Several members of the type II transmembrane serine protease (TTSP) family have been shown to play critical roles in cancer progression; however, many family members have not yet been characterized in malignancy. We identified TMPRSS13 transcript to be upregulated in CRC compared to normal colon. This increase was confirmed …

Examining The Involvement Of Slx5 In The Apoptotic Response To Chronic Activation Of The Spindle Assembly Checkpoint, Pinar Buket Atalay, Eli̇f Ergi̇n Çavuşoğlu, Öykü Aşci, Duygu Aygüneş

Turkish Journal of Biology

Microtubule-targeting agents represent one of the most successful groups of anticancer drugs used in cancer therapy today. These drugs induce a prolonged mitotic arrest through chronic spindle assembly checkpoint (SAC) activation. Apoptosis, an outcome of the prolonged mitotic arrest, is the main mechanism by which these anticancer drugs kill cancer cells. However, not much is known about the mechanism that directs chronic SAC activation to apoptosis among other possible outcomes. The aim of this study is to investigate whether Slx5, a sumo-targeted ubiquitin E3 ligase, is involved in directing chronic SAC activation to apoptosis. We show that chronic SAC activation …

A Novel 1,4-Naphthoquinone-Derived Compound Induces Apoptotic Cell Deathin Breast Cancer Cells, Di̇dem Karakaş Zeybek, Remzi̇ Okan Akar, Zeli̇ha Gökmen, Nahi̇de Gülşah Deni̇z, Engi̇n Ulukaya

Turkish Journal of Biology

Breast cancer is the most-diagnosed cancer type among women. The triple-negative subtype is an especially aggressive type of breast cancer. Although chemotherapy is almost the only option for the treatment of triple-negative breast cancer (TNBC), currently used chemotherapeutics are not effective enough, considering the poor survival rate of patients. Therefore, novel compounds need to be developed to improve survival rates. It has been known that quinonic compounds, which are found in nature, have antibacterial, antifungal, and antitumorigenic properties. Naphthoquinones are members of the quinone family and are widely used in research due to their promising properties. In this study, we …

Crosstalk Between Autophagy And Apoptosis Induced By Camphor Inschizosaccharomyces Pombe, Hizlan Hincal Ağuş, Sedanur Yilmaz, Cansin Ogeday Şengöz

Turkish Journal of Biology

Camphor is widely used in pharmacy, the food industry, and cosmetics. In this study, we evaluate inhibitory and cytotoxic effects of camphor in the fission yeast (Schizosaccharomyces pombe), which presents a unicellular model in mechanistic toxicology and cell biology. Low-dose camphor exposure (0.4 mg/mL) activated autophagy, which was shown by GFP-Atg8 dots and transcriptional upregulation of Atg6 (Beclin-1 ortholog). Autophagy was also confirmed by using autophagy-deficient cells, which showed reduction in GFP-Atg8 dot formation. However, high-dose camphor exposure (0.8 mg/mL) caused dramatic cell death ratios, demonstrated by spot and colony-forming assays, even in autophagy-deficient cells. To unravel the underlying mechanism, …

In Silico Approach To The Analysis Of Snps In The Human Apaf1 Gene, Tuğba Kaman, Ömer Faruk Karasakal, Ebru Özkan Oktay, Korkut Ulucan, Muhsi̇n Konuk

Turkish Journal of Biology

The apoptotic protease activating factor 1 (APAF1) gene encodes a cytoplasmic protein that initiates apoptosis and is a crucial factor in the mitochondria-dependent death pathway. APAF1 is implicated in many pathways such as apoptosis, neurodegenerative diseases, and cancer. The purpose of this study was to predict deleterious/damaging SNPs in the APAF1 gene via in silico analysis. To this end, APAF1 missense SNPs were obtained from the NCBI dbSNP database. In silico analysis of the missense SNPs was carried out by using publicly available online software tools. The stabilization and three-dimensional modeling of mutant proteins were also determined by using the …

Nanosecond Pulsed Electric Fields Induce Endoplasmic Reticulum Stress Accompanied By Immunogenic Cell Death In Murine Models Of Lymphoma And Colorectal Cancer, Alessandra Rossi, Olga N. Pakhomova, Peter A. Mollica, Maura Casciola, Uma Mangalanathan, Andrei G. Pakhomov, Claudia Muratori

Bioelectrics Publications

Depending on the initiating stimulus, cancer cell death can be immunogenic or non-immunogenic. Inducers of immunogenic cell death (ICD) rely on endoplasmic reticulum (ER) stress for the trafficking of danger signals such as calreticulin (CRT) and ATP. We found that nanosecond pulsed electric fields (nsPEF), an emerging new modality for tumor ablation, cause the activation of the ER-resident stress sensor PERK in both CT-26 colon carcinoma and EL-4 lymphoma cells. PERK activation correlates with sustained CRT exposure on the cell plasma membrane and apoptosis induction in both nsPEF-treated cell lines. Our results show that, in CT-26 cells, the activity of …