Medical Biochemistry Commons^™

Mechanisms Of Therapeutic Resistance In Castration Resistant Prostate Cancer, Sarah Katherine Martin

Theses and Dissertations--Molecular and Cellular Biochemistry

Taxane based chemotherapy is an effective treatment for castration-resistant prostate cancer (CRPC) via stabilization of microtubules. Progression to castration-resistant prostate cancer is characterized by increased androgen receptor (AR), elevated intra-prostatic androgens and activated AR signaling despite castrate levels of androgens.

Previous studies identified that the inhibitory effect of microtubule targeting chemotherapy on AR activity was conferred by interfering with AR intracellular trafficking. The N-terminal domain (NTD) of AR was identified as a tubulin interacting domain that can be effectively targeted by the novel small molecular inhibitor, EPI. Taken together, this evidence provided the rationale that targeting AR nuclear translocation and …

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 …

Inhibition Of Mtor Signaling Protects Against Myocardial Reperfusion Injury, Acute Myocardial Infarction, Scott M. Filippone

Theses and Dissertations

Acute myocardial infarction (AMI) is the leading cause of death worldwide. Currently, the best method of treating cardiac ischemia is early reperfusion which, itself, induces myocardial damage. The mTOR complex is a key regulator of cardioprotection against cell stressors. We hypothesized that reperfusion therapy with Rapamycin, a potent mTOR inhibitor, would reduce infarct size in adult mouse hearts. Rapamycin was administered at the onset of reperfusion following 30 min in situ LAD ligation. After 24 hours of reperfusion, myocardial infarct size and apoptosis were significantly reduced in rapamycin-treated mice compared to control. Rapamycin inhibited pro-apoptotic protein Bax and phosphorylation of …

Analysis Of Drug Interactions With Lipoproteins By High Performance Affinity Chromatography, Matthew R. Sobansky

Department of Chemistry: Dissertations, Theses, and Student Research

High density lipoprotein (HDL), low density lipoprotein (LDL), and very low density lipoprotein (VLDL) are lipoproteins previously shown to bind many basic and neutral hydrophobic drugs in serum. These interactions impact the distribution, delivery, metabolism, and excretion of drugs and are important in determining drug activity, pharmacokinetics, and toxicity in the human body. Information about drug-lipoprotein interactions and the strength of these interactions can be useful in determining the distribution of drugs following administration.

The research presented in this dissertation uses high performance affinity chromatography (HPAC) and packed columns to study binding of the drug propranolol to immobilized lipoproteins such …

Saturated Free Fatty Acids Induce Cholangiocyte Lipoapoptosis, Sathish Kumar Natarajan, Sally A. Ingham, Ashley M. Mohr, Cody J. Wehrkamp, Anuttoma Ray, Sohini Roy, Sophie C. Cazanave, Mary A. Smith, Justin L. Mott

Journal Articles: Biochemistry & Molecular Biology

Recent studies have identified a cholestatic variant of nonalcoholic fatty liver disease (NAFLD) with portal inflammation and ductular reaction. Based on reports of biliary damage, as well as increased circulating free fatty acids (FFAs) in NAFLD, we hypothesized the involvement of cholangiocyte lipoapoptosis as a mechanism of cellular injury. Here, we demonstrate that the saturated FFAs palmitate and stearate induced robust and rapid cell death in cholangiocytes. Palmitate and stearate induced cholangiocyte lipoapoptosis in a concentration-dependent manner in multiple cholangiocyte-derived cell lines. The mechanism of lipoapoptosis relied on the activation of caspase 3/7 activity. There was also a significant up-regulation …

Mrp4-Dependent Regulation Of Fibroblast Migration, Chandrima Sinha

Theses and Dissertations (ETD)

Roles of cyclic nucleotides and cyclic nucleotide-dependent signaling molecules in regulating several signaling pathways including cell migration have long been known. However, the new and revolutionary concept is that it is not just the absence or presence of cyclic nucleotides, but a highly coordinated balance between these molecules regulates cell migration. Multi-drug resistance protein 4 (MRP4), is a member of the large family of ATP binding cassette (ABC) transporter proteins, that localizes to the plasma membrane and functions as a nucleotide efflux transporter and thus plays a pivotal role in the regulation of intracellular cyclic nucleotide dynamics. In our study …

Strengths And Weaknesses Of Hybrid Tpr Technology For Obtaining Structural And Mechanistic Insights Into Tpr Proteins, Shanshan Yu

Theses and Dissertations (ETD)

Tetratricopeptide (TPR) repeats are a 34-residue helix-turn-helix motif that when repeated pack into a superhelical structure. TPR domains are frequently found mediating protein-protein interactions, often through a central groove. One protein complex bearing numerous TPR repeats is the Anaphase Promoting Complex (APC). The anaphase-promoting complex (APC) is a multi-subunit complex, which orchestrates mitotic cell cycles. APC is an E3 ligase in the ubiquitin cascade, and directs the 26S proteosome degradation of cell-cycle regulators. Throughout mitotic progression, proteins that are key regulators of the cell cycle are assembled with polyubiquitin chains by APC.

One domain of the human APC is comprised …

Modulation Of T Lymphocytes By Tumor-Released Survivin, Jessica Marie Jutzy

Loma Linda University Electronic Theses, Dissertations & Projects

The tumor microenvironment is an area of intense interaction between normal and malignant cells. Factors and cell types within this environment can play a crucial role in the progression or regression of the tumor. Of primary interest are tumor-infiltrating T lymphocytes, which have been shown to have a key role in modifying the dynamics of the tumor microenvironment to promote or prevent tumor growth. While there is much in vitro and in vivo evidence for a modification of the tumor infiltrating T cell population toward a pro-tumor environment, what induces these changes within the tumor microenvironment has remained elusive. Our …

Novel Insights Into The Role Of The Smoothened Cysteine Rich Domain In Hedgehog Signalling, Rajashree Rana

Theses and Dissertations (ETD)

The Hedgehog (Hh) signal transduction pathway functions as one of the key developmental pathways and deranged Hh signalling is associated with numerous cancer and tumor conditions. The Smoothened (Smo) G protein coupled receptor (GPCR) functions as the signal transducer of the Hh pathway and is the most attractive drug target of the pathway. The structure of the Smo receptor includes seven membrane spanning domains, extracellular and intracellular loops connecting the membranous domains and the extracellular cysteine rich domain (CRD). The extracellular CRD of the Smo receptor is homologous to the Frizzled (FzD) CRD. The FzD CRD interacts with the physiological …

Screening For Novel Inhibitors Of Αlpha-Ynuclein Seeded Nucleation-Dependent Aggregation And Toxicity As A Potential Therapeutic Strategy For Parkinson’S Disease, Mustafa Taleb Ardeh

Dissertations

α-Synuclein aggregation is the key pathogenic event in several important neurological disorders including Parkinson’s Disease, dementia with Lewy bodies and multiple system atrophy, giving rise to a distinct group of neurodegenerative diseases known as synucleinopathies. Although the molecular basis of α-syn toxicity has not been precisely elucidated, recent studies indicate that α-syn toxicity is mediated by a nucleation-dependent aggregation process. To elucidate the structural basis of α-synuclein mediated toxicity, we developed various methods to prepare different α-synuclein species of a defined size and morphology distribution, and we investigated their toxicity in different human dopaminergic cell lines. We observed that crude …

Role Of Host Micrornas In Kaposi's Sarcoma-Associated Herpesvirus Pathogenesis, Zhiqiang Qin, Francesca Peruzzi, Krzysztof Reiss, Lu Dai

School of Medicine Faculty Publications

MicroRNAs (miRNAs) are small non-coding RNA species that can bind to both untranslated and coding regions of target mRNAs, causing their degradation or post-transcriptional modification. Currently, over 2500 miRNAs have been identified in the human genome. Burgeoning evidence suggests that dysregulation of human miRNAs can play a role in the pathogenesis of a variety of diseases, including cancer. In contrast, only a small subset of human miRNAs has been functionally validated in the pathogenesis of oncogenic viruses, in particular, Kaposi's sarcoma-associated herpesvirus (KSHV). KSHV is the etiologic agent of several human cancers, such as primary effusion lymphoma (PEL) and Kaposi's …

Computer-Aided Structure-Based Drug Discovery: Cxcl12, P. Aeruginosa Lpxa, And The Tiam1 Pdz Domain, Emmanuel William Smith

USF Tampa Graduate Theses and Dissertations

For structure-based drug discovery, structural information of a target protein is necessary. NMR, or X-ray crystallography can provide necessary information on active site configuration that can lead a successful virtual screening campaign into identifying binders that may then be optimized into potent inhibitors. However, many challenges exist in the structure-based drug discovery cycle. For instance, structure determination of a protein of interest can many times be a daunting task. In addition, complex structure determination, which can allow essential characterization of protein-ligand interactions, is also challenging and many times impossible. Virtual screening heavily relies on such structural information, but hit-to-lead optimization …

Peptide Arrays For Detecting Naphthenic Acids In Oil Sands Process Affected Water, Kamaljit Kaur, Subir Bhattacharjee, Rajesh G. Pillai, Sahar Ahmed, Sarfuddin Azmi

Pharmacy Faculty Articles and Research

Naphthenic acids (NAs) are water-soluble components of petroleum. The characterization and quantification of NAs by analytical methods have proved quite challenging, whilst the toxic effects of these water-soluble compounds on a variety of organisms adversely affecting reproduction and steroid production is becoming apparent. In this study, we report a fluorescence-based competitive binding method for rapid sensing of the presence of NAs using cellulosic peptide array strips as sensors. The peptide array was designed from sequences derived from the estrogen receptor (ER). Several of these peptides were able to detect the presence of NAs at low micromolar (∼5 mg L^{−1 …}

Rgs16, A Novel P53 And Prb Cross-Talk Candidate Inhibits Migration And Invasion Of Pancreatic Cancer Cells, Miranda B. Carper, James Denvir, Goran Boskovic, Donald A. Primerano, Pier Paolo Claudio

Biochemistry and Microbiology

Data collected since the discovery of p53 and pRb/RB1 suggests these tumor suppressors cooperate to inhibit tumor progression. Patients who have mutations in both p53 and RB1 genes have increased tumor reoccurrence and decreased survival compared to patients with only one tumor suppressor gene inactivated. It remains unclear how p53 and pRb cooperate toward inhibiting tumorigenesis. Using RNA expression profiling we identified 179 p53 and pRb cross-talk candidates in normal lung fibroblasts (WI38) cells exogenously coexpressing p53 and pRb. Regulator of G protein signaling 16 (RGS16) was among the p53 and pRb cross-talk candidates and has been implicated in inhibiting …

Er-Associated Degradation And Cadmium Dependent Rescue Of Pca1, Nathan Smith

Department of Biochemistry: Dissertations, Theses, and Student Research

Protein synthesis and proper folding is an essential process for all organisms. In eukaryotes proteins of the secretory pathway are synthesized and inserted into the lumen or membrane of the endoplasmic reticulum. Eukaryotic cells maintain a mechanism for removal of proteins unable to fold properly. This process is known as ER-associated degradation (ERAD). A poorly functioning ERAD can lead to a build-up of misfolded proteins which has been implicated in several degenerative diseases such as Alzheimer’s, Amyotrophic lateral sclerosis, and Parkinson’s. Thus, the study of how proteins are recognized, extracted from the ER, and degraded is essential for determining methods …

Helicobacter-Pylori Negative Gastritis In Children—A New Clinical Enigma, Yoram Elitsur, Deborah L. Preston

Biochemistry and Microbiology

The decrease in the prevalence of Helicobacter pylori (Hp) infection in children in the world gave rise to a new pathological finding termed as Hp-negative gastritis. Unfortunately, the term “Hp-negative gastritis” has not been identified as a pathological process and has the status of a “second cousin”; in most publications it was never mentioned as a subject to be dealt with, but was “left over” data that was never the topic of the manuscripts’ discussions. Only recently has the topic captured the attention of the pathologists who described this phenomenon in adults, yet the pathological and/or clinical spectrum or significance …

Mmu-Mir-615-3p Regulates Lipoapoptosis By Inhibiting C/Ebp Homologous Protein., Yasuhiro Miyamoto, Amy S Mauer, Swarup Kumar, Justin L. Mott, Harmeet Malhi

Journal Articles: Biochemistry & Molecular Biology

Lipoapoptosis occurring due to an excess of saturated free fatty acids such as palmitate is a key pathogenic event in the initiation of nonalcoholic fatty liver disease. Palmitate loading of cells activates the endoplasmic reticulum stress response, including induction of the proapoptotic transcription factor C/EBP homologous protein (CHOP). Furthermore, the loss of microRNAs is implicated in regulating apoptosis under conditions of endoplasmic reticulum (ER) stress. The aim of this study was to identify specific microRNAs regulating CHOP expression during palmitate-induced ER stress. Five microRNAs were repressed under palmitate-induced endoplasmic reticulum stress conditions in hepatocyte cell lines (miR-92b-3p, miR-328-3p, miR-484, miR-574-5p, …

Ethanol-Induced Oxidant Stress Modulates Hepatic Autophagy And Proteasome Activity., Terrence M. Donohue, Paul G. Thomes

Journal Articles: Biochemistry & Molecular Biology

In this review, we describe research findings on the effects of alcohol exposure on two major catabolic systems in liver cells: the ubiquitin-proteasome system (UPS) and autophagy. These hydrolytic systems are not unique to liver cells; they exist in all eukaryotic tissues and cells. However, because the liver is the principal site of ethanol metabolism, it sustains the greatest damage from heavy drinking. Thus, the focus of this review is to specifically describe how ethanol oxidation modulates the activities of the UPS and autophagy and the mechanisms by which these changes contribute to the pathogenesis of alcohol-induced liver injury. Here, …

Withaferin A Alone And In Combination With Cisplatin Suppresses Growth And Metastasis Of Ovarian Cancer By Targeting Putative Cancer Stem Cells., Sham S. Kakar, Mariusz Z. Ratajczak, Karen S. Powell, Mana Moghadamfalahi, Donald M. Miller, Surinder K. Batra, Sanjay K. Singh

Journal Articles: Biochemistry & Molecular Biology

Currently, the treatment for ovarian cancer entails cytoreductive surgery followed by chemotherapy, mainly, carboplatin combined with paclitaxel. Although this regimen is initially effective in a high percentage of cases, unfortunately within few months of initial treatment, tumor relapse occurs because of platinum-resistance. This is attributed to chemo-resistance of cancer stem cells (CSCs). Herein we show for the first time that withaferin A (WFA), a bioactive compound isolated from the plant Withania somnifera, when used alone or in combination with cisplatin (CIS) targets putative CSCs. Treatment of nude mice bearing orthotopic ovarian tumors generated by injecting human ovarian epithelial cancer cell …

Unbiased Analysis Of Pancreatic Cancer Radiation Resistance Reveals Cholesterol Biosynthesis As A Novel Target For Radiosensitisation., Joshua J. Souchek, Michael J. Baine, Chi Lin, Satyanarayana Rachagani, Suprit Gupta, Sukhwinder Kaur, K Lester, D Zheng, S Chen, Lynette Smith, A Lazenby, Sonny L. Johansson, Maneesh Jain, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Despite its promise as a highly useful therapy for pancreatic cancer (PC), the addition of external beam radiation therapy to PC treatment has shown varying success in clinical trials. Understanding PC radioresistance and discovery of methods to sensitise PC to radiation will increase patient survival and improve quality of life. In this study, we identified PC radioresistance-associated pathways using global, unbiased techniques.

METHODS: Radioresistant cells were generated by sequential irradiation and recovery, and global genome cDNA microarray analysis was performed to identify differentially expressed genes in radiosensitive and radioresistant cells. Ingenuity pathway analysis was performed to discover cellular pathways …

Selection Of An Eevolved Orthogonal Ne-Acetyllysine Trnasynthetase That Can Incorporate The Unnantural Amino Acid L-Homocitrulline Site-Specifically Into Proteins, Jaclyn Alatrash, Camelia Baleanu Gogonea, Stanly L. Hazen, Joseph Didonato

Undergraduate Research Posters 2014

Oxidatively damaged apolipoprotein A1 (apoA1, the main protein constituent of high density lipoprotein (HDL) - the “good cholesterol”) has been isolated from circulating plasma and atherosclerosis plaque with modification of lysine amino acid residues to homocittruline (carbamyllysine) in apoA1 identified as a modification found increased in smokers that correlates with elevated cardiovascular risk for myocardial infarction (MI), stoke or death. The selected carbamyllysine tRNA synthetase will then be used to express a series of human apoA1 alleles containing amber codons in place of various lysine residues and assayed for its ability to form nascent HDL particles and to activate NF-κB …

Enhanced Expression Of Codon Optimized Mycobacterium Avium Subsp. Paratuberculosis Antigens In Lactobacillus Salivarius, Christopher D. Johnston, John P. Bannatine, Rodney Govender, Lorraine Endersen, Daniel Pletzer, Helge Weingart, Aidan Coffey, Jim O'Mahony, Roy D. Sleator

Department of Biological Sciences Publications

It is well documented that open reading frames containing high GC content show poor expression in A+T rich hosts. Specifically, G+C-rich codon usage is a limiting factor in heterologous expression of Mycobacterium avium subsp. paratuberculosis (MAP) proteins using Lactobacillus salivarius. However, re-engineering opening reading frames through synonymous substitutions can offset codon bias and greatly enhance MAP protein production in this host. In this report, we demonstrate that codon-usage manipulation of MAP2121c can enhance the heterologous expression of the major membrane protein (MMP), analogous to the form in which it is produced natively by MAP bacilli. When heterologously over-expressed, antigenic determinants …

Histological Evaluation Of The Cryo-Destruction Of The Zona Glomerulosa (Outermost Layer) Of The Adrenal Cortex, Huda Ahmed, Jonida Pone

Journal of Undergraduate Research at Minnesota State University, Mankato

The outer portion, or cortex, of the adrenal gland produces three hormones, two of which are highly critical to normal function of the body. The cortex itself is divided into three layers, each responsible for a certain hormone synthesis. The outermost layer (zona glomerulosa) produces aldosterone, a hormone involved in the regulation of body sodium, blood volume, and blood pressure. The middle layer produces co rticosterone, a hormone that is active in a variety of biological functions, and necessary for life. Due to its effects on blood volume, aldosterone has been implicated in the development of hypertension, or high blood …

Heat Release Of Polyurethanes Containing Potential Flame Retardants Based On Boron And Phosphorus Chemistries, Vladimir Benin, Bastien Gardelle, Alexander Morgan

Chemistry Faculty Publications

Using a polyurethane of methylene diphenyl isocyanate and 1,3-propane diol, several new non-halogenated aromatic boron and phosphorus flame retardants were evaluated for heat release reduction potential using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods, and were then analyzed via spectroscopic methods to determine if the flame retardant was still present in the final product. PCFC testing on the resulting products showed that the flame retardant molecule can have different effects on heat release depending upon how it is mixed into the polyurethane. Some …

Self-Assembled Gold Nanoplexes For Cancer-Targeted Sirna Delivery, Yongliang Shi

Master's Theses

Through layer-by-layer method, the authors have constructed three Au nanoplexes: AuPEI/RNA/PEI, AuPEI/RNA/PEI-mPEG, and AuPEI/NA/PEI-PEG-FA. All the nanoplexes are characterized by UV-vis spectrometry, DLS, and zeta potential. The surface density of the first layer PEI and second layer RNA were also determined. Moreover, the Au nanoplexes can protect siRNA from RNase degradation and are stable in cell culture medium.

siGLuc-ppp, ssRNA₈₀, and siF17 were delivered by the assembled Au nanoplexes, and the results were analyzed by GLuc assay, TB assay, and Luciferase assay. In terms of RNA delivery, the Au nanoplexes AuPEI/RNA/PEI exhibited excellent gene silencing efficiency (or causing …

Novel Role Of Pancreatic Differentiation 2 In Facilitating Self-Renewal And Drug Resistance Of Pancreatic Cancer Stem Cells., Arokia P. Vaz, Moorthy P. Ponnusamy, Satyanarayana Rachagani, P Dey, Apar Kishor Ganti, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Cancer stem cells (CSCs) contribute towards disease aggressiveness and drug resistance. Specific identification of CSC maintenance genes and targeting can improve the efficiency of currently available treatment modalities. Pancreatic differentiation 2 (PD2) has a major role in the self-renewal of mouse embryonic stem cells. In the present study, we investigated the role of PD2 in pancreatic CSCs.

METHODS: Characterisation of CSCs and non-CSCs from mouse models, pancreatic cancer cells and human tissues by CSC and self-renewal marker analysis using confocal assay. Effect of PD2 knockdown in CSCs (after gemcitabine treatment) was studied by immunoblot and apoptosis assays.

RESULTS: A …

Stag2 Promotes Error Correction In Mitosis By Regulating Kinetochore–Microtubule Attachments, Marianna Kleyman, Lilian Kabeche, Duane A. Compton

Dartmouth Scholarship

Mutations in the STAG2 gene are present in ∼20% of tumors from different tissues of origin. STAG2 encodes a subunit of the cohesin complex, and tumors with loss-of-function mutations are usually aneuploid and display elevated frequencies of lagging chromosomes during anaphase. Lagging chromosomes are a hallmark of chromosomal instability (CIN) arising from persistent errors in kinetochore-microtubule (kMT) attachment. To determine whether the loss of STAG2 increases the rate of formation of kMT attachment errors or decreases the rate of their correction, we examined mitosis in STAG2-deficient cells. STAG2 depletion does not impair bipolar spindle formation or delay mitotic progression. Instead, …

A Concise Review On The Current Understanding Of Pancreatic Cancer Stem Cells., Arokia P. Vaz, Moorthy P. Ponnusamy, Parthasarathy Seshacharyulu, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

No abstract provided.

Determination Of Corrosion Inhibitor Lubricity Improver In Jet Fuel By Liquid Chromatography-Electrospray Ionization Mass Spectrometry, David W. Johnson, Milissa Flake, Ryan Adams

Chemistry Faculty Publications

Military jet fuel (JP-8) is very similar to commercial jet fuel (Jet A) except for the presence of three additives, fuel system icing inhibitor, corrosion inhibitor–lubricity improver (CI-LI), and antistatic additive, which are added to improve characteristics of JP-8. Of particular interest is the CI-LI additive; the most common active ingredient is a dimer of linoleic acid. This article focuses on quantification of the active ingredient in the CI-LI additive by liquid chromatography–mass spectrometry (LC–MS). This method will allow the determination of CI-LI content in military jet fuel samples.

Pd2/Paf1 Depletion In Pancreatic Acinar Cells Promotes Acinar-To-Ductal Metaplasia., Parama Dey, Satyanarayana Rachagani, Arokia P. Vaz, Moorthy P. Ponnusamy, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Pancreatic differentiation 2 (PD2), a PAF (RNA Polymerase II Associated Factor) complex subunit, is overexpressed in pancreatic cancer cells and has demonstrated potential oncogenic property. Here, we report that PD2/Paf1 expression was restricted to acinar cells in the normal murine pancreas, but its expression increased in the ductal cells of KrasG12D/Pdx1Cre (KC) mouse model of pancreatic cancer with increasing age, showing highest expression in neoplastic ductal cells of 50 weeks old mice. PD2/Paf1 was specifically expressed in amylase and CK19 double positive metaplastic ducts, representing intermediate structures during pancreatic acinar-to-ductal metaplasia (ADM). Similar PD2/Paf1 expression was observed in murine pancreas …