Biochemistry Commons^™

Novel Treatments For Pxe: Targeting The Systemic And Local Drivers Of Ectopic Calcification, Ida Joely Jacobs, Qiaoli Li

Department of Biochemistry and Molecular Biology Faculty Papers

Pseudoxanthoma elasticum (PXE) is a heritable multisystem ectopic calcification disorder. The gene responsible for PXE, ABCC6, encodes ABCC6, a hepatic efflux transporter regulating extracellular inorganic pyrophosphate (PPi), a potent endogenous calcification inhibitor. Recent studies demonstrated that in addition to the deficiency of plasma PPi, the activated DDR/PARP signaling in calcified tissues provides an additional possible mechanism of ectopic calcification in PXE. This study examined the effects of etidronate (ETD), a stable PPi analog, and its combination with minocycline (Mino), a potent inhibitor of DDR/PARP, on ectopic calcification in an Abcc6-/- mouse model of PXE. Abcc6-/- mice, at 4 weeks of …

Combination Therapy Of Triple-Negative Breast Cancer With Paclitaxel And Ambrisentan, A Selective Antagonist Of The Endothelin Type A Receptor, Inhibits Tumor Growth And Metastasis, Farah Nasser Almahrook

Theses

Cancer treatment is a big challenge especially when associated with metastasis. Moreover, the importance of using combination therapy is increasing, especially for highly invasive, drug-resistant cancers, such as triple-negative breast cancer (TNBC). Ambrisentan, a selective antagonist of the endothelin type A receptor (ETAR) was previously shown to reduce metastasis of TNBC in a preclinical tumor model when used prophylactically. In the current study, we investigated the therapeutic potential of Ambrisentan, given as monotherapy or in combination with Paclitaxel, on TNBC. The data show that oral dosing with Ambrisentan led to a significant retardation in tumor growth and metastasis. Moreover, combining …

Structural Insights Into The Cl-Par-4 Protein: Ionic Requirements, Conformational Transitions, And Interaction With Cisplatin, Krishna Kumar Raut

Chemistry & Biochemistry Theses & Dissertations

Cancer continues to be the leading global cause of death, with challenges in early diagnosis, drug resistance, non-specific drug targeting, and cancer recurrence and metastasis posing formidable obstacles in cancer therapy. In this context, Prostate Apoptosis Response-4 (Par-4), a pro-apoptotic tumor suppressor protein, emerged as a promising therapeutic target due to its ability to selectively induce apoptosis in cancer cells, thereby minimizing the drug-associated adverse effects. However, a comprehensive understanding of the structural features of Par-4, specifically the caspase-cleaved fragment (cl-Par-4), is crucial for therapeutic advancements.

This dissertation investigated the effects of various ions, both monovalent and divalent, on the …

Copy Number Variation That Influences The Ionizing Radiation Sensitivity Of Oral Squamous Cell Carcinoma, Tadahide Izumi, Piotr G. Rychahou, Li Chen, Molly H. Smith, Joseph Valentino

Markey Cancer Center Faculty Publications

Genome instability in cancer cells causes not only point mutations but also structural variations of the genome, including copy number variations (CNVs). It has recently been proposed that CNVs arise in cancer to adapt to a given microenvironment to survive. However, how CNV influences cellular resistance against ionizing radiation remains unknown. PRMT5 (protein arginine methyltransferase 5) and APE1 (apurinic/apyrimidinic endonuclease 1), which enhance repair of DNA double-strand breaks and oxidative DNA damage, are closely localized in the chromosome 14 of the human genome. In this study, the genomics data for the PRMT5 and APE1 genes, including their expression, CNVs, and …

Distinct Camp Signaling Microdomains Differentially Regulate Melanosomal Ph And Pigmentation, Maftuna Yusupova, Dalee Zhou, Jaewon You, Jeydi Gonzalez-Guzman, Megha B. Ghanta, Hong Pu, Zalfa Abdel-Malek, Qiuying Chen, Steven S. Gross, John August D'Orazio, Shosuke Ito, Kazumasa Wakamatsu, Melissa L. Harris, Jonathan H. Zippin

Markey Cancer Center Faculty Publications

cAMP signaling is a well-established regulator of melanin synthesis. Two distinct cAMP signaling pathways—the transmembrane adenylyl cyclase pathway, activated primarily by the MC1R, and the soluble adenylyl cyclase (sAC) pathway—affect melanin synthesis. The sAC pathway affects melanin synthesis by regulating melanosomal pH, and the MC1R pathway affects melanin synthesis by regulating gene expression and post-translational modifications. However, whether MC1R genotype affects melanosomal pH is poorly understood. We now report that loss of function MC1R does not affect melanosomal pH. Thus, sAC signaling appears to be the only cAMP signaling pathway that regulates melanosomal pH. We also addressed whether MC1R genotype …

Phosphatidic Acid Binding To Patched Contributes To The Inhibition Of Smoothened And Hedgehog Signaling In Drosophila Wing Development, Jie Zhang, Yajuan Liu, Chi Wang, Craig W. Vander Kooi, Jianhang Jia

Markey Cancer Center Faculty Publications

Hedgehog (Hh) signaling controls growth and patterning during embryonic development and homeostasis in adult tissues. Hh binding to the receptor Patched (Ptc) elicits intracellular signaling by relieving Ptc-mediated inhibition of the transmembrane protein Smoothened (Smo). We uncovered a role for the lipid phosphatidic acid (PA) in the regulation of the Hh pathway in Drosophila melanogaster. Deleting the Ptc C-terminal tail or mutating the predicted PA-binding sites within it prevented Ptc from inhibiting Smo in wing discs and in cultured cells. The C-terminal tail of Ptc directly interacted with PA in vitro, an association that was reduced by Hh, and increased …

Regulated Translocation Of Neutral Sphingomyelinase-2 To The Plasma Membrane Drives Insulin Resistance In Steatotic Hepatocytes, Salim S. El-Amouri, Alexander A. Karakashian, Erhard Bieberich, Mariana N. Nikolova‑Karakashian

Markey Cancer Center Faculty Publications

Abstract Obesity-associated diabetes is linked to the accumulation of ceramide in various organs, including the liver. The exact mechanisms by which ceramide contributes to diabetic pathology are unclear, but one proposed scenario is that ceramide accumulation may inhibit insulin signaling pathways. It is unknown however whether the excess ceramide is generated proximal to the insulin receptor, that is, at the plasma membrane (PM), where it could affect the insulin signaling pathway directly, or the onset of insulin resistance is due to ceramide- induced mitochondrial dysfunction and/or lipotoxicity. Using hepatic cell lines and primary cultures, gain- and loss- of function approach, …

Hiv-1 Vpu Protein Forms Stable Oligomers In Aqueous Solution Via Its Transmembrane Domain Self-Association, Saman Majeed, Lan Dang, Md Majharul Islam, Olamide Ishola, Peter P Borbat, Steven J Ludtke, Elka R Georgieva

Faculty, Staff and Students Publications

We report our findings on the assembly of the HIV-1 protein Vpu into soluble oligomers. Vpu is a key HIV-1 protein. It has been considered exclusively a single-pass membrane protein. Previous observations show that this protein forms stable oligomers in aqueous solution, but details about these oligomers still remain obscure. This is an interesting and rather unique observation, as the number of proteins transitioning between soluble and membrane embedded states is limited. In this study we made use of protein engineering, size exclusion chromatography, cryoEM and electron paramagnetic resonance (EPR) spectroscopy to better elucidate the nature of the soluble oligomers. …

Protocol For Optimizing Production And Quality Control Of Infective Ecohiv Virions, Hammodah Rawhi Hammodah Alfar, Daphne N. Pariser, Harry Chanzu, Smita Joshi, Daniёlle M. Coenen, Joshua Lykins, Kanakanagavalli Shravani Prakhya, Mary Jane Potash, Wei Chao, Jennifer Kelschenbach, David J. Volsky, Kelly Metcalf-Pate

Saha Cardiovascular Research Center Faculty Publications

EcoHIV is a model of HIV infection that recapitulates aspects of HIV-1 pathology in mice. However, there are limited published protocols to guide EcoHIV virion production. Here, we present a protocol for producing infective EcoHIV virions and essential quality controls. We describe steps for viral purification, titering, and multiple techniques to analyze infection efficacy. This protocol produces high infectivity in C57BL/6 mice which will aid investigators in generating preclinical data.

Bacteroides Fragilis In The Gut Microbiomes Of Alzheimer’S Disease Activates Microglia And Triggers Pathogenesis In Neuronal C/Ebpβ Transgenic Mice, Yiyuan Xia, Yifan Xiao, Zi-Hao Wang, Ashfaqul M. Alam, John P. Haran, Beth A. Mccormick, Xiji Shu, Xiaochuan Wang, Keqiang Ye

Markey Cancer Center Faculty Publications

Gut dysbiosis contributes to Alzheimer’s disease (AD) pathogenesis, and Bacteroides strains are selectively elevated in AD gut microbiota. However, it remains unknown which Bacteroides species and how their metabolites trigger AD pathologies. Here we show that Bacteroides fragilis and their metabolites 12-hydroxy-heptadecatrienoic acid (12-HHTrE) and Prostaglandin E2 (PGE2) activate microglia and induce AD pathogenesis in neuronal C/EBPβ transgenic mice. Recolonization of antibiotics cocktail-pretreated Thy1-C/EBPβ transgenic mice with AD patient fecal samples elicits AD pathologies, associated with C/EBPβ/Asparaginyl endopeptidase (AEP) pathway upregulation, microglia activation, and cognitive disorders compared to mice receiving healthy donors’ fecal microbiota transplantation (FMT). Microbial 16S rRNA sequencing …

Unleashing The Potential Of 1,3-Diketone Analogues As Selective Lh2 Inhibitors, Juhoon Lee, Hou-Fu Guo, Shike Wang, Yazdan Maghsoud, Erik Antonio Vázquez-Montelongo, Zhifeng Jing, Rae M. Sammons, Eun Jeong Cho, Pengyu Ren, G. Andrés Cisneros, Jonathan M. Kurie, Kevin N. Dalby

Markey Cancer Center Faculty Publications

Lysyl hydroxylase 2 (LH2) catalyzes the formation of highly stable hydroxylysine aldehyde-derived collagen cross-links (HLCCs), thus promoting lung cancer metastasis through its capacity to modulate specific types of collagen cross-links within the tumor stroma. Using 1 and 2 from our previous high-throughput screening (HTS) as lead probes, we prepared a series of 1,3-diketone analogues, 1−18, and identified 12 and 13 that inhibit LH2 with IC50’s of approximately 300 and 500 nM, respectively. Compounds 12 and 13 demonstrate selectivity for LH2 over LH1 and LH3. Quantum mechanics/molecular mechanics (QM/MM) modeling indicates that the selectivity of 12 and 13 may stem from …

Nanodiscs: A Novel Approach To The Study Of The Methionine Abc Transporter System, Michael T. Winslow

Master's Theses

Membrane transporter proteins play the vital role of moving compounds in and out of the cell and are essential for all living organisms. ATP Binding Cassette (ABC) family transporters function both as importers and exporters in prokaryotes. MetNI is an E. coli Type I ABC transporter responsible for the uptake of methionine into the cytosol from the cell periplasmic space through the cell membrane to maintain intracellular methionine pools. ABC transporters, like other membrane proteins, are most often mechanistically and structurally studied in vitro, solubilized by detergents. However, detergent micelles may affect the conformational changes of membrane proteins relative to …

Relationship Between Plasma Fluoride Levels, Glutathione Peroxidase Activity, Hemoglobin, And Abortion In Rural And Urban Pregnant Women From Settat (Morocco), Lalla Asmaa Katir Masnaoui, Abdellatif Rahim, Habiba Bouchab, Bouchra El Amiri, Boubker Nasser, Essamadi Abdel Khalid

Makara Journal of Health Research

Background: This study aimed to investigate the relationship between plasma fluoride and hemoglobin levels, glutathione peroxidase (GPx) activity, and abortion among rural and urban pregnant women from Settat province (Morocco).

Methods: Blood samples were collected from rural pregnant women who had not undergone abortion (N = 224), rural pregnant women who had an abortion (N = 38), urban pregnant women who had not undergone abortion (N = 163), and urban pregnant women who had an abortion (N = 14).

Results: The highest (p < 0.01) plasma fluoride levels and the lowest (p < 0.01) GPx activity were observed in rural pregnant women. In all participants, plasma fluoride levels were significantly higher (p < 0.001), and the GPx activity was significantly (p < 0.001) lower in pregnant women who had an abortion compared with those who did not undergo such process. No significant difference was observed between the hemoglobin levels of all participants. Furthermore, abortion was positively correlated with plasma fluoride levels (p < 0.001) and negatively correlated with GPx activity (p < 0.001) in rural participants.

Conclusions: Rural pregnant women had higher plasma …

Determining The Existence And Regulation Of Microlipophagy In Primary Brown And White Adipocytes, Sara C. Arenas De Leon

Biomedical Sciences ETDs

Lipids are one of life’s four main macromolecules and provide essential functions to cells.

The degradation of lipid droplets and mobilization of lipids occurs through lipolysis. Emerging evidence demonstrates evidence of a selective form of autophagy in lipolysis. The process of microlipophagy has only recently been described, and many features of its regulation are still poorly understood. Our recent study showed that inhibiting mammalian target of rapamycin complex 1 (mTORC1) pathway by depletion of Raptor in adipocytes led to an influx of lysosomes and accumulation of lipid droplets within lysosome. Here, we expand on these previous findings. We were able …

Co-Targeting Nucleus Accumbens Associate 1 And Nf-Κb Signaling Synergistically Inhibits Melanoma Growth, Lixiang Gu, Xingcong Ren, Chrispus Ngule, Xiaofang Xiong, Jianxun Song, Zhiguo Li, Jin-Ming Yang

Markey Cancer Center Faculty Publications

Nucleus-accumbens-associated protein-1 (NAC1) is a cancer-related transcriptional factor encoded by the NACC1 gene, which is amplified and overexpressed in various human cancers and has been appreciated as one of the top potential cancer driver genes. NAC1 has therefore been explored as a potential therapeutic target for managing malignant tumors. Here, we show that NAC1 is a negative regulator of NF-κB signaling, and NAC1 depletion enhances the level of the nuclear NF-κB in human melanoma. Furthermore, the inhibition of NF-κB signaling significantly potentiates the antineoplastic activity of the NAC1 inhibition in both the cultured melanoma cells and xenograft tumors. This study …

Metabolic Disruption Induced By Mtor Signaling Pathway Inhibition In Regulatory T-Cell Expansion For Clinical Application, Roberto Gedaly, Gabriel Orozco, Alexandre P. Ancheta, Mackenzie Donoho, Siddharth Desai, Fanny Chapelin, Aman Khurana, Lillie J. Lewis, Cuiping Zhang, Francesc Marti

Markey Cancer Center Faculty Publications

Background: Regulatory T cell (Treg) therapy is considered an alternative approach to induce tolerance in transplantation. If successful, this therapy may have implications on immunosuppression minimization/withdrawal to reduce drug-induced toxicity in patients. The aim of this study was to assess the efficacy of the mTORC1/C2 inhibitor, AZD8055, in the manufacturing of clinically competent Treg cells and compare the effects with those induced by rapamycin (RAPA), another mTOR inhibitor commonly used in Treg expansion protocols.

Methods: Primary human Treg cells were isolated from leukapheresis product. Cell viability, expansion rates, suppressive function, autophagy, mitochondrial unfolded protein response (mitoUPR), and cell metabolic profile …

The S1p Receptor 1 Antagonist Ponesimod Reduces Tlr4-Induced Neuroinflammation And Increases Aβ Clearance In 5xfad Mice, Zhihui Zhu, Liping Zhang, Ahmed Elsherbini, Simone M. Crivelli, Priyanka Tripathi, Carmen Harper, Zainuddin Quadri, Stefka D. Spassieva, Erhard Bieberich

Markey Cancer Center Faculty Publications

Background Previously, we showed that the sphingosine-1-phosphate (S1P) transporter spinster 2 (Spns2) mediates activation of microglia in response to amyloid β peptide (Aβ). Here, we investigated if Ponesimod, a functional S1P receptor 1 (S1PR1) antagonist, prevents Aβ-induced activation of glial cells and Alzheimer’s disease (AD) pathology.

Methods We used primary cultures of glial cells and the 5XFAD mouse model to determine the effect of Aβ and Ponesimod on glial activation, Aβ phagocytosis, cytokine levels and pro-inflammatory signaling pathways, AD pathology, and cognitive performance.

Findings Aβ42 increased the levels of TLR4 and S1PR1, leading to their complex formation. Ponesimod prevented the …

A Cost-Effective And Smart Sensing Tissue-Like Testbed For Surgical Training, Lysette Zaragoza

McNair Research Journal SJSU

A low-cost tissue-like testbed with six nodes of varying stiffness was developed for surgical training to provide pressure and force feedback data through image reception to human operators. Using SolidWorks, a 3D model of the box trainer housing was created. A pad for the distribution of smartsensing nodes and microcontroller connections was designed with open spaces for the respective components. The pad was 3D-printed with PLA filament. Flat piezoelectric pressure sensors were fabricated with conductive materials and velostat sensor material. Using static and dynamic analyses, three top sensors were chosen to be used in three pressure sensing nodes. A calibration …

High-Resolution Cryo-Em Structure Of The Pseudomonas Bacteriophage E217, Fenglin Li, Chun-Feng Hou, Ravi K. Lokareddy, Ruoyu Yang, Francesca Forti, Federica Briani, Gino Cingolani

Department of Biochemistry and Molecular Biology Faculty Papers

E217 is a Pseudomonas phage used in an experimental cocktail to eradicate cystic fibrosis-associated Pseudomonas aeruginosa. Here, we describe the structure of the whole E217 virion before and after DNA ejection at 3.1 Å and 4.5 Å resolution, respectively, determined using cryogenic electron microscopy (cryo-EM). We identify and build de novo structures for 19 unique E217 gene products, resolve the tail genome-ejection machine in both extended and contracted states, and decipher the complete architecture of the baseplate formed by 66 polypeptide chains. We also determine that E217 recognizes the host O-antigen as a receptor, and we resolve the N-terminal portion …

Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker

Department of Biochemistry and Molecular Biology Faculty Papers

Fibrosis, or excessive scarring, is characterized by the emergence of alpha-smooth muscle actin (αSMA)-expressing myofibroblasts and the excessive accumulation of fibrotic extracellular matrix (ECM). Currently, there is a lack of effective treatment options for fibrosis, highlighting an unmet need to identify new therapeutic targets. The acquisition of a fibrotic phenotype is associated with changes in chromatin structure, a key determinant of gene transcription activation and repression. The major repressive histone mark, H3K27me3, has been linked to dynamic changes in gene expression in fibrosis through alterations in chromatin structure. H3K27-specific homologous histone methylase (HMT) enzymes, Enhancer of zeste 1 and 2 …

Invited Review: Adrenocortical Function In Avian And Non-Avian Reptiles: Insights From Dispersed Adrenocortical Cells., Rocco V. Carsia, Patrick J. Mcilroy, Henry B John-Alder

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Herein we review our work involving dispersed adrenocortical cells from several lizard species: the Eastern Fence Lizard (Sceloporus undulatus), Yarrow's Spiny Lizard (Sceloporus jarrovii), Striped Plateau Lizard (Sceloporus virgatus) and the Yucatán Banded Gecko (Coleonyx elegans). Early work demonstrated changes in steroidogenic function of adrenocortical cells derived from adult S. undulatus associated with seasonal interactions with sex. However, new information suggests that both sexes operate within the same steroidogenic budget over season. The observed sex effect was further explored in orchiectomized and ovariectomized lizards, some supported with exogenous testosterone. Overall, a suppressive effect of testosterone was evident, especially in cells …

Long-Term Monitoring Of Clodronate In Equine Hair Using Liquid Chromatography-Tandem Mass Spectrometry, Heather K. Knych, D. S. Mckemie, S. Yim, S. D. Stanley, R. M. Arthur

UK CARES Faculty Publications

Given the potential for long-term inhibition of bone remodeling/healing and detrimental effects to horses in training, bisphosphonates are tightly regulated in horseracing. Hair has proven to be an effective matrix for detection of drug administration to horses and has been particularly effective in detecting drugs for a long period of time post administration. Thus, hair may prove to be a useful matrix for detection of administration of this class of drugs. The objective of the current study was to develop an assay and assess the usefulness of hair as a matrix for long-term detection of clodronate to horses. Seven horses …

Enhanced Bypass Of Pd-L1 Translation Reduces The Therapeutic Response To Mtor Kinase Inhibitors, Yanan Cao, Qing Ye, Murong Ma, Qing-Bai She

Markey Cancer Center Faculty Publications

Increased PD-L1 expression in cancer cells is known to enhance immunosuppression, but the mechanism underlying PD-L1 upregulation is incompletely characterized. We show that PD-L1 expression is upregulated through internal ribosomal entry site (IRES)-mediated translation upon mTORC1 inhibition. We identify an IRES element in the PD-L1 50-UTR that permits cap-independent translation and promotes continuous production of PD-L1 protein despite effective inhibition of mTORC1. eIF4A is found to be a key PD-L1 IRES-binding protein that enhances PD-L1 IRES activity and protein production in tumor cells treated with mTOR kinase inhibitors (mTORkis). Notably, treatment with mTORkis in vivo elevates PD-L1 levels and reduces …

Messes: Software For Transforming Messy Research Datasets Into Clean Submissions To Metabolomics Workbench For Public Sharing, P. Travis Thompson, Hunter N. B. Moseley

Markey Cancer Center Faculty Publications

In recent years, the FAIR guiding principles and the broader concept of open science has grown in importance in academic research, especially as funding entities have aggressively promoted public sharing of research products. Key to public research sharing is deposition of datasets into online data repositories, but it can be a chore to transform messy unstructured data into the forms required by these repositories. To help generate Metabolomics Workbench depositions, we have developed the MESSES (Metadata from Experimental SpreadSheets Extraction System) software package, implemented in the Python 3 programming language and supported on Linux, Windows, and Mac operating systems. MESSES …

The Metabolomics Workbench File Status Website: A Metadata Repository Promoting Fair Principles Of Metabolomics Data, Christian D. Powell, Hunter N. B. Moseley

Markey Cancer Center Faculty Publications

Background: An updated version of the mwtab Python package for programmatic access to the Metabolomics Workbench (MetabolomicsWB) data repository was released at the beginning of 2021. Along with updating the package to match the changes to MetabolomicsWB’s ‘mwTab’ file format specification and enhancing the package’s functionality, the included validation facilities were used to detect and catalog file inconsistencies and errors across all publicly available datasets in MetabolomicsWB.

Results: The MetabolomicsWB File Status website was developed to provide continuous validation of MetabolomicsWB data files and a useful interface to all found inconsistencies and errors. This list of detectable issues/errors include format …

Amyloid-Beta Protein Concentration Dependence Of Reversible Aggregation Using Gold Colloid Particles, Renee Spencer, Lila Kocieniewski, Bryan Martinez, Kazushige Yokoyama

McNair Scholars Program

Although Alzheimer’s and COVID-19 are different diseases, the commonality between them is during the process of them developing in a person by fibrillogenesis. The product of fibrillogenesis results in the development of these diseases. We study the first stage of fibrillogenesis where the amyloid-beta peptide monomers are assembled into an oligomer. We want to isolate this oligomer using gold colloids because this step can be reversed. Utilizing gold colloids allows us to freeze fibrillogenesis in the first step by folding and unfolding the protein repeatedly through a series of pH changes from 4 or below to 10 or higher. At …

Metals And Metal Complexes In Diseases With A Focus On Covid-19: Facts And Opinions, Agnieszka Ścibior, Manuel Aureliano, Alvin A. Holder, Juan Llopis

Chemistry & Biochemistry Faculty Publications

In the present Special Issue on “Metals and Metal Complexes in Diseases with a Focus on COVID-19: Facts and Opinions”, an attempt has been made to include reports updating our knowledge of elements considered to be potential candidates for therapeutic applications and certain metal-containing species, which are extensively being examined towards their potential biomedical use due to their specific physicochemical properties. The Special Issue compiles data on the role of metals in COVID-19 and focuses on other illnesses and biological processes that affect metal metabolism. It consists of eight manuscripts, including five review articles and three original research papers (Figure …

Multi-Target Ligand-Guided Selection (Ligs) Against B-Cell Specific Antigens Expressed In A Single Lymphoma Cell Population, Nicole B. Williams

Dissertations, Theses, and Capstone Projects

Nucleic acid ligands called aptamers are single-stranded DNA or RNA molecules which fold into functional three-dimensional structures to facilitate their target binding with high affinity and specificity. The method used to generate aptamers is an in vitro process called Systematic Evolution of Ligands by Exponential enrichment (SELEX). A variant of SELEX, cell-SELEX has been used to select aptamers against cell-surface proteins in their native state. We recently introduced a novel method called Ligand-Guided Selection (LIGS) to identify aptamers against cell-surface markers. Herein, we expanded LIGS method into a multiplexing platform to partition multiple aptamers against B-cell-specific antigens, CD19 and CD20, …

Differential Inhibition Of Anaplerotic Pyruvate Carboxylation And Glutaminolysis-Fueled Anabolism Underlies Distinct Toxicity Of Selenium Agents In Human Lung Cancer, Teresa W-M Fan, Jason Winnike, Ahmad Al-Attar, Alex C. Belshoff, Pawel Lorkiewicz, Jin Lian Tan, Min Wu, Richard M. Higashi, Andrew N. Lane

Markey Cancer Center Faculty Publications

Past chemopreventive human trials on dietary selenium supplements produced controversial outcomes. They largely employed selenomethionine (SeM)-based diets. SeM was less toxic than selenite or methylseleninic acid (MSeA) to lung cancer cells. We thus investigated the toxic action of these Se agents in two non-small cell lung cancer (NSCLC) cell lines and ex vivo organotypic cultures (OTC) of NSCLC patient lung tissues. Stable isotope-resolved metabolomics (SIRM) using 13C6-glucose and 13C5,15N2-glutamine tracers with gene knockdowns were employed to examine metabolic dysregulations associated with cell type- and treatment-dependent phenotypic changes. Inhibition of key anaplerotic processes, pyruvate carboxylation (PyC) and glutaminolysis were elicited by …

Noncovalent Interactions That Tune The Reactivities Of The Flavins In Bifurcating Electron Transferring Flavoprotein, María González-Viegas, Rajiv K. Kar, Anne-Frances Miller, Maria-Andrea Mroginski

Markey Cancer Center Faculty Publications

Bifurcating electron transferring flavoproteins (Bf-ETFs) tune chemically identical flavins to two contrasting roles. To understand how, we used hybrid quantum mechanical molecular mechanical calculations to characterize noncovalent interactions applied to each flavin by the protein. Our computations replicated the differences between the reactivities of the flavins: the electron transferring flavin ( ETflavin) was calculated to stabilize anionic semiquinone (ASQ) as needed to execute its single-electron transfers, whereas the Bf flavin (Bfflavin) was found to disfavor the ASQ state more than does free flavin and to be less susceptible to reduction. The stability of ETflavin ASQ was attributed in part to …