Life Sciences Commons^™

Mechanistic Insights Into The Regulation Of Mitochondrial Fission By Cyclin C, Vidyaramanan Ganesan, Katrina F Cooper, Randy Strich

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Cyclin C is a component of the mediator complex of RNA polymerase II that localizes to the nucleus under normal conditions. In response to stress, cyclin C translocates to the cytosol and mitochondria and mediates stress‐induced mitochondrial fission and apoptosis. The molecular mechanisms by which cyclin C induces mitochondrial fission are unknown. Using in vitro experimental approaches, we sought to investigate the mechanistic basis of cyclin C mediated mitochondrial fission.

The Role Of Mapk And Scf In The Destruction Of Med13 In Cyclin C Mediated Cell Death, David C Stieg, Stephen D Willis, Joseph Scuorzo, Mia Song, Vidyaramanan Ganesan, Randy Strich, Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

In response to stress, the yeast¹ and mammalian² cyclin C translocate from the nucleus to the cytoplasm, where it associates with the GTPase Drp1/Dnm1 to drive mitochondrial fragmentation and apoptosis. Therefore, the decision to release cyclin C represents a key life or death decision. In unstressed cells, the cyclin C‐Cdk8 kinase regulates transcription by associating with the Mediator of RNA polymerase II. We previously reported that the Mediator component Med13 anchors cyclin C in the nucleus³. Loss of Med13 function leads to constitutive cytoplasmic localization of cyclin C, resulting in fragmented mitochondria, hypersensitivity to stress and …

Perturbing Anti-Apoptotic Proteins To Develop Novel Cancer Therapies, Jacob Contreras

Theses & Dissertations

The apoptotic pathway involves a tightly regulated network of proteins which respond to various stimuli. Previous studies have indicated Mcl-1 and Bcl-xL are intimately involved in determining cell fate, and if both are concurrently neutralized, it activates the apoptotic pathway. The inactivation of Bcl-xL and Mcl-1 as a mechanism to trigger the intrinsic apoptotic response can be used as a platform to develop therapeutic strategies to target cancer cells. The apoptotic pathway is largely dysregulated and often leads to therapy resistance in cancer cells. Although direct inhibitors of Bcl-xL have been developed and have advanced to clinical trials, development of …

Investigating The Regulatory Circuitry Of Protein Kinases And Proteases In Apoptosis, Stephanie A. Zukowski

Electronic Thesis and Dissertation Repository

Apoptosis is a tightly regulated cellular process essential for normal development and tissue homeostasis. Perturbations to apoptotic signaling underscores numerous pathogenic processes emphasizing the importance of apoptotic regulation. During apoptosis, caspases orchestrate cellular degradation through proteolytic cleavage of key structural and enzymatic proteins. In a different manner, protein kinases regulate apoptosis by catalyzing the post-translational phosphorylation of substrate proteins to facilitate either pro- or anti-apoptotic signal transduction pathways. Emerging paradigms have indicated that bidirectional crosstalk between protein kinases and caspases serves to globally fine-tune the equilibrium between signals directing cell survival and cell death. In this regard, identifying points of …

Endonucleolytic Cleavage In The Expansion Segment 7 Of 25s Rrna Is An Early Marker Of Low-Level Oxidative Stress In Yeast, Daniel Shedlovskiy, Jessica A Zinskie, Ethan Gardner, Dimitri G Pestov, Natalia Shcherbik

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

The ability to detect and respond to oxidative stress is crucial to the survival of living organisms. In cells, sensing of increased levels of reactive oxygen species (ROS) activates many defensive mechanisms that limit or repair damage to cell components. The ROS-signaling responses necessary for cell survival under oxidative stress conditions remain incompletely understood, especially for the translational machinery. Here, we found that drug treatments or a genetic deficiency in the thioredoxin system that increase levels of endogenous hydrogen peroxide in the yeast Saccharomyces cerevisiae promote site-specific endonucleolytic cleavage in 25S ribosomal RNA (rRNA) adjacent to the c loop of …

Cd80 Expressed By Cd8+ T Cells Contributes To Pd-L1-Induced Apoptosis Of Activated Cd8+ T Cells, Meagan R. Rollins, Rachel M. Gibbons Johnson

Biology Publications

Tumor cells are capable of limiting antitumor CD8+ T cell responses through their cell surface expression of PD-L1. In addition to PD-1 expressed by CD8+ T cells, PD-L1 also binds to CD80 expressed by CD8+ T cells. The influence of the PD-L1/CD80 interaction on CD8+ T cell function has not been fully characterized, so we sought to investigate the impact of the PD-L1/CD80 interaction on PD-L1-induced apoptosis of activated CD8+ T cells. We found that CD8+ T cells that lacked CD80 expression got activated to the same extent as wild-type CD8+ T cells, but when cultured with anti-CD3 and PD-L1/Fc …

Loss Of Fructose-1,6-Bisphosphatase Induces Glycolysis And Promotes Apoptosis Resistance Of Cancer Stem-Like Cells: An Important Role In Hexavalent Chromium-Induced Carcinogenesis, Jin Dai, Yanli Ji, Wei Wang, Donghern Kim, Leonard Yenwong Fai, Lei Wang, Jia Luo, Zhuo Zhang

Toxicology and Cancer Biology Faculty Publications

Hexavalent chromium (Cr(VI)) compounds are confirmed human carcinogens for lung cancer. Our previous studies has demonstrated that chronic exposure of human bronchial epithelial BEAS-2B cells to low dose of Cr(VI) causes malignant cell transformation. The acquisition of cancer stem cell-like properties is involved in the initiation of cancers. The present study has observed that a small population of cancer stem-like cells (BEAS-2B-Cr-CSC) exists in the Cr(VI)-transformed cells (BEAS-2B-Cr). Those BEAS-2B-Cr-CSC exhibit extremely reduced capability of generating reactive oxygen species (ROS) and apoptosis resistance. BEAS-2B-Cr-CSC are metabolic inactive as evidenced by reductions in oxygen consumption, glucose uptake, ATP production, and lactate …

The Role Of Nucleolin Phosphorylation By Ck2 In Regulating Cellular Fate Under Normal And Stress Conditions, Shu Xiao

Dissertations, Theses, and Capstone Projects

Nucleolin (NCL or C23) is an abundant genotoxic stress-responsive RNA binding phosphoprotein. NCL constitutes 10% of total nucleolar protein that has functions in multiple biological processes, including ribosome biogenesis, DNA/RNA metabolism, cellular response to DNA damage, cell growth, proliferation and death. In this dissertation, I elucidate the role of nucleolin phosphorylation by casein kinase 2 (CK2) in controlling cellular fate by regulating p53 checkpoint under normal and stressed conditions. First, I demonstrate that the six consensus CK2 sites on the N-terminus of NCL are important for cell survival and proliferation. Expression of CK2 phosphorylation-deficient NCL mutant leads to dominant negative …

Oxidative Stress-Induced Jnk/Ap-1 Signaling Is A Major Pathway Involved In Selective Apoptosis Of Myelodysplastic Syndrome Cells By Withaferin-A, Karine Z. Oben, Sara S. Alhakeem, Mary Kathryn Mckenna, Jason A. Brandon, Rajeswaran Mani, Sunil K. Noothi, Jinpeng Liu, Shailaja Akunuru, Sanjit Kumar Dhar, Inder P. Singh, Ying Liang, Chi Wang, Ahmed Abdel-Latif, Harold F. Stills Jr., Daret K. St Clair, Hartmut Geiger, Natarajan Muthusamy, Kaoru Tohyama, Ramesh C. Gupta, Subbarao Bondada

Markey Cancer Center Faculty Publications

Myelodysplastic syndromes (MDS) are a diverse group of malignant clonal hematopoietic stem cell disorders characterized by ineffective hematopoiesis, dysplastic cell morphology in one or more hematopoietic lineages, and a risk of progression to acute myeloid leukemia (AML). Approximately 50% of MDS patients respond to current FDA-approved drug therapies but a majority of responders relapse within 2-3 years. There is therefore a compelling need to identify potential new therapies for MDS treatment. We utilized the MDS-L cell line to investigate the anticancer potential and mechanisms of action of a plant-derived compound, Withaferin A (WFA), in MDS. WFA was potently cytotoxic to …

A Naturally Generated Decoy Of The Prostate Apoptosis Response-4 Protein Overcomes Therapy Resistance In Tumors, Nikhil Hebbar, Ravshan Burikhanov, Nidhi Shukla, Shirley Qiu, Yanming Zhao, Kojo S. J. Elenitoba-Johnson, Vivek M. Rangnekar

Radiation Medicine Faculty Publications

Primary tumors are often heterogeneous, composed of therapy-sensitive and emerging therapy-resistant cancer cells. Interestingly, treatment of therapy-sensitive tumors in heterogeneous tumor microenvironments results in apoptosis of therapy-resistant tumors. In this study, we identify a prostate apoptosis response-4 (Par-4) amino-terminal fragment (PAF) that is released by diverse therapy-sensitive cancer cells following therapy-induced caspase cleavage of the tumor suppressor Par-4 protein. PAF caused apoptosis in cancer cells resistant to therapy and inhibited tumor growth. A VASA segment of Par-4 mediated its binding and degradation by the ubiquitin ligase Fbxo45, resulting in loss of Par-4 proapoptotic function. Conversely, PAF, which contains this VASA …

The Regulation Of Rotavirus–Infected Ht29.F8 And Ma104 Cells Treated With Arachidin 1 Or Arachidin 3, Caleb M. Witcher

Electronic Theses and Dissertations

Rotavirus (RV) infections cause severe life threatening diarrhea in young children and immunocompromised individuals. Several effective vaccines have been developed for young children but are not protective against all strains of RV, and there are no anti-RV therapeutics. Our laboratory has discovered a decrease in the number of infectious simian RV particles (SA114f) in human intestinal cell line, HT29.f8 cells with the addition of either of two stilbenoids, arachidin-1 (A1) or arachidin-3 (A3). This suggests effects on the host cell and RV replication. We examined the cellular effects of human RV strain (Wa) on a human intestinal cell line (HT29.f8) …

Identifying The Signaling Mechanisms Of Egfr-Mediated Apoptosis., Nicole Marion Jackson

Electronic Theses and Dissertations

The Epidermal Growth Factor Receptor (EGFR) is a 170-kilodalton transmembrane protein that belongs to the ErbB family of receptor tyrosine kinases. Upon ligand-mediated activation, the EGFR is responsible for cell growth, proliferation, and tissue homeostasis; however, the EGFR is overexpressed in many human malignancies, including MDA-MB-468 cells, a metastatic breast epithelial cell line. Studies within this cell line, and other cell lines characterized with high EGFR levels, have shown that EGF stimulation results in the induction of apoptosis. However, the mechanisms and signaling effectors implicated in this process have yet to be elucidated. The overarching research goal of this dissertation …

Gene 33/Mig6 Regulates Apoptosis And The Dna Damage Response Through Independent Mechanisms, Cen Li, Soyoung Park, Leonard M. Eisenberg, Hong Zhao, Zbigniew Darzynkiewicz, Dazhong Xu

NYMC Faculty Posters

Gene 33 (Mig6, ERRFI1) is an inducible adaptor/scaffold protein whose expression can be induced by both stress and mitogenic signals. It contains multiple domains for protein-protein interaction and is involved in a broad spectrum of cellular functions. Gene 33 promotes apoptosis in a cell type-dependent manner. A recent study has linked Gene 33 to the DNA damage response (DDR) induced by hexavalent chromium [Cr(VI)]. Here we show that Gene 33 induces apoptosis via both c-Abl/p73 and EGFR/AKT-dependent pathways in lung epithelial and lung carcinoma cells. Ectopic expression of Gene 33 also triggers DDR in an ATM-dependent fashion and through pathways …

Exploitation And Regulation Of Apoptotic Caspases, Scott Eron

Doctoral Dissertations

Caspases are the cysteine proteases that govern apoptotic cell death. The regulation of these enzymes is critical in order to restrain their death-inducing capabilities until the appropriate moment. Infidelity of caspase regulation and activation underlies a plethora of human diseases ranging from cancer to neurodegeneration. This establishes a pressing need for comprehensive studies of the apoptotic caspases in order to understand all aspects of their regulation, activation, substrate preferences, structure, and function. A detailed structural view of caspase regulation would have lasting implications for future therapeutic avenues targeting caspase function or apoptosis. This dissertation chronicles caspase regulation by phosphorylation as …

Relb Expression Determines The Differential Effects Of Ascorbic Acid In Normal And Cancer Cells, Xiaowei Wei, Yong Xu, Fang Fang Xu, Luksana Chaiswing, David M. Schnell, Teresa Noel, Chi Wang, Jinfei Chen, Daret K. St. Clair, William H. St. Clair

Toxicology and Cancer Biology Faculty Publications

Cancer cells typically experience higher oxidative stress than normal cells, such that elevating pro-oxidant levels can trigger cancer cell death. Although pre-exposure to mild oxidative agents will sensitize cancer cells to radiation, this pre-exposure may also activate the adaptive stress defense system in normal cells. Ascorbic acid is a prototype redox modulator that when infused intravenously appears to kill cancers without injury to normal tissues; however, the mechanisms involved remain elusive. In this study, we show how ascorbic acid kills cancer cells and sensitizes prostate cancer to radiation therapy while also conferring protection upon normal prostate epithelial cells against radiation-induced …

Radiation Induced Apoptosis Of Murine Bone Marrow Cells Is Independent Of Early Growth Response 1 (Egr1), Karine Z. Oben, Beth W. Gachuki, Sara S. Alhakeem, Mary Kathryn Mckenna, Ying Liang, Daret K. St. Clair, Vivek M. Rangnekar, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

An understanding of how each individual 5q chromosome critical deleted region (CDR) gene contributes to malignant transformation would foster the development of much needed targeted therapies for the treatment of therapy related myeloid neoplasms (t-MNs). Early Growth Response 1 (EGR1) is a key transcriptional regulator of myeloid differentiation located within the 5q chromosome CDR that has been shown to regulate HSC (hematopoietic stem cell) quiescence as well as the master regulator of apoptosis—p53. Since resistance to apoptosis is a hallmark of malignant transformation, we investigated the role of EGR1 in apoptosis of bone marrow cells; a cell population from which …

Chloroquine-Inducible Par-4 Secretion Is Essential For Tumor Cell Apoptosis And Inhibition Of Metastasis, Ravshan Burikhanov, Nikhil Hebbar, Sunil K. Noothi, Nidhi Shukla, James Sledziona, Nathália Araujo, Meghana Kudrimoti, Qing Jun Wang, David S. Watt, Danny R. Welch, Jodi Maranchie, Akihiro Harada, Vivek M. Rangnekar

Radiation Medicine Faculty Publications

The induction of tumor suppressor proteins capable of cancer cell apoptosis represents an attractive option for the re-purposing of existing drugs. We report that the anti-malarial drug, chloroquine (CQ), is a robust inducer of Par-4 secretion from normal cells in mice and cancer patients in a clinical trial. CQ-inducible Par-4 secretion triggers paracrine apoptosis of cancer cells and also inhibits metastatic tumor growth. CQ induces Par-4 secretion via the classical secretory pathway that requires the activation of p53. Mechanistically, p53 directly induces Rab8b, a GTPase essential for vesicle transport of Par-4 to the plasma membrane prior to secretion. Our findings …

Oocyte Development In Melanogryllus Desertus (Pallas, 1771) (Orthoptera: Gryllidae):Presence Of Balbiani Body, Özlem Çakici

Turkish Journal of Zoology

Oocyte development in the ovary of the black cricket, Melanogryllus desertus, was investigated. In the panoistic ovary of M. desertus, oocyte developmental stages based on their histological properties were classified as previtellogenic, vitellogenic, and maturation. Oocytes were encircled by follicle cells through the developmental stages. In the previtellogenic stage, a few vacuoles were observed just beneath the oolemma. At the beginning of the vitellogenic stage, subdivided into early-, middle-, and late-vitellogenic stages, yolk granules within the oocyte were initially observed just beneath the oolemma. In addition, small lipid droplets were initially present under the yolk granules. As vitellogenesis proceeded, both …

Kruppel-Like Factor 2 In Cholangiocarcinoma, Cody J. Wehrkamp, Justin L. Mott

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Tenofovir Induced Nephrotoxicity: A Mechanistic Study, Rachel A. Murphy

Theses, Dissertations and Capstones

Tenofovir (TFV) is a reverse transcriptase inhibitor that is approved by the United States Food and Drug Administration (FDA) to treat HIV and chronic Hepatitis B. It has a long half-life, allowing for once a day dosing and is effective in treatment of both naive and experienced patients. It is administered orally as tenofovir disoproxil fumarate (TDF) and is deesterified in plasma to the active drug TFV. However, renal impairment is associated with its use; TFV can induce decreased glomerular filtration rate (GFR) and free calcitriol, renal failure, and Fanconi Syndrome. The exact mechanism of toxicity currently remains unknown, largely …

The Prohibitin Protein Complex Promotes Mitochondrial Stabilization And Cell Survival In Hematologic Malignancies, Elisa Robles Escajeda

Open Access Theses & Dissertations

Lymphocyte proliferation and differentiation is coordinated with high precision in healthy humans and is vital to maintaining a normal immune system. Imbalance of these events can result in the development of autoimmune diseases, immunodeficiencies and hematopoietic malignancies. These pathologies, specifically leukemia and lymphoma have a high incidence of relapse and mortality due to limited treatment options. Therefore, there is a critical need to characterize the signal transduction pathways and understand molecular hallmarks that mediate T cell activation in order to develop new strategies for diagnosis and treatments of these diseases.

Prohibitins (PHB1 and PHB2) have been proposed to play important …

Using Rainbow Trout Cell Lines As A Model For Understanding The Innate Anti-Fv3 Immune Response, Graeme Robert Jones Lisser

Theses and Dissertations (Comprehensive)

Ranavirus infections are on the rise and have been implicated in numerous species die-offs across the globe. Frog virus 3 (FV3) is the type-species of the genus, yet the immune mechanisms governing susceptibility remain poorly understood. Arguably the most important immune response to infection is the type I interferon (IFN) response. Type I IFNs trigger an “antiviral state” in host cells via the production of numerous interferon-stimulated genes (ISGs) that act to inhibit virus replication in various way, including the induction of apoptosis. Apoptosis is an important antiviral defense mechanism to limit virus replication within infected cells. This study employed …

Tumor Necrosis Factor-Alpha Induced Caspase-3 Activation-Related Inos Gene Expression In Adp-Activated Platelets, Özge Çevi̇k, Zelal Adigüzel, Ahmet Tarik Baykal, Azi̇ze Şener

Turkish Journal of Biology

Platelets are sensitive cells and are easily activated by different stimulants in the circulation system. It is known that tumor necrosis factor-alpha (TNF-α) is a proinflammatory cytokine and plays a role in inflammation. The role of TNF-α in the apoptotic process in blood platelets is unknown. In order to study the formation of apoptosis in platelets after incubation with TNF-α and/or ADP, several biomarkers were chosen: phosphatidylserine (PS) exposure and P-selectin binding; cGMP, Cyt-c, and Ca2+ levels and NOS activation; and gene and protein expression of caspase-3 and iNOS. Platelets were incubated with 100 pg/mL TNF-α and/or 50 mM iNOS …

Microrna-34a Regulates Brain-Derived Neurotrophic Factorin An Intracerebral Hemorrhage Model, Jin Hee Kim, Jae-Sun Choi

Turkish Journal of Biology

Intracerebral hemorrhages (ICHs) are devastating neurological events frequently resulting in a serious negative prognosis. The exact physiological and disease processes involved in ICHs are complex, but are thought to involve microRNAs (miRNAs), 22 nucleotide small noncoding RNAs that control a variety of normal physiological and disease processes. In this study, we show that a miRNA, miR-34a, regulates BDNF in a model of ICH injury. In particular, we assessed the impact of AM34a, an inhibitor of miR-34a, on the toxicity of thrombin-induced apoptosis and on BDNF-mediated signaling. We investigated the increased expression of miR-34a after an ICH-induced thrombin toxicity injury using …

Changes In Apoptosis-Related Gene Expression Profiles In Cancer Cell Lines Exposed To Usnic Acid Lichen Secondary Metabolite, Adnan Berk Di̇nçsoy, Demet Cansaran Duman

Turkish Journal of Biology

The presence of uninhibited side effects of cancer drugs often used in cancer treatment has stimulated the search for alternative therapeutic approaches. Therefore, anticarcinogenic effects of synthetic, herbal, and fungal drugs have been investigated for the treatment of various cancer types in recent studies. Lichens, symbiotic organisms of fungi and algae, synthesize metabolites with significant biological activities. The aim of the current study was to screen the anticancer potential of usnic acid on various types of nonmalignant cell lines (Vero, L929) and cancer cell lines (CaCo2, RD, Hep2C, HepG2, Wehi). The growth inhibitory effect of usnic acid was determined by …

Combination Of Esomeprazole With Chemotherapeutics Results In More Pronounced Cytotoxic Effect Via Apoptosis On A549 Nonsmall-Cell Lung Cancer Cell Line, Arzu Yilmaztepe Oral, Haluk Barbaros Oral, Mehmet Sarimahmut, Buse Cevatemre, Güven Özkaya, Şeni̇z Korkmaz, Engi̇n Ulukaya

Turkish Journal of Biology

The vacuolar (H+)-ATPases that pump H+ from the cytoplasm to extracellular compartments can alter the pH of the tumor microenvironment. Esomeprazole can effectively inhibit vacuolar (H+)-ATPases and may increase the effectiveness of chemotherapeutics. Therefore, we used esomeprazole in combination with cisplatin, carboplatin, paclitaxel, docetaxel, gemcitabine, and vinorelbine on the A549 nonsmall-cell lung cancer cell line. Cisplatin and carboplatin combinations with esomeprazole exhibited superior cytotoxicity compared to the other selected chemotherapeutics. Low-dose combinations of esomeprazole with either cisplatin or carboplatin resulted in synergistic interaction. We examined cytotoxic activity of these combinations with the xCELLigence real-time cytotoxicity assay and detected that esomeprazole …