Pharmacy and Pharmaceutical Sciences Commons^™

Broad-Spectrum Activity Of Membranolytic Cationic Macrocyclic Peptides Against Multi-Drug Resistant Bacteria And Fungi, Sandeep Lohan, Anastasia G. Konshina, Rakesh K. Tiwari, Roman G. Efremov, Innokentiy Maslennikov, Keykavous Parang

Pharmacy Faculty Articles and Research

The emergence of multidrug-resistant (MDR) strains causes severe problems in the treatment of microbial infections owing to limited treatment options. Antimicrobial peptides (AMPs) are drawing considerable attention as promising antibiotic alternative candidates to combat MDR bacterial and fungal infections. Herein, we present a series of small amphiphilic membrane-active cyclic peptides composed, in part, of various nongenetically encoded hydrophilic and hydrophobic amino acids. Notably, lead cyclic peptides 3b and 4b showed broad-spectrum activity against drug-resistant Gram-positive (MIC = 1.5–6.2 µg/mL) and Gram-negative (MIC = 12.5–25 µg/mL) bacteria, and fungi (MIC = 3.1–12.5 µg/mL). Furthermore, lead peptides displayed substantial antibiofilm action comparable …

Polymeric Nanocarriers For Delivery Of Small Molecules Inhibiting Tubulin Polymerization For The Treatment Of Pancreatic Cancer And Lung Metastatic Melanoma, Rajan Sharma Bhattarai

Theses & Dissertations

The aim of this thesis is to develop delivery systems for the novel small molecules which inhibit tubulin polymerization. One of the small molecules was modified to lipid conjugate to increase the lipophilicity of the molecules which in turn drastically improved the drug loading in amphiphilic polymeric system. The second molecule was conjugated to the amphiphilic polymeric backbone with pH sensitive Schiff’s linker for the tumor site specific delivery in lung metastatic melanoma model.

Chapter 1 discusses the tumor microenvironment for the solid tumor especially focusing on Pancreatic Ductal Adenocarcinoma (PDAC). Further the drug delivery system currently researched for addressing …

Method For Designing Compounds And Compositions Useful For Targeting High Stoichiometric Complexes To Treat Conditions, Including Treatment Of Viruses, Bacteria, And Cancers Having Acquired Drug Resistance, Peixuan Guo, Dan Shu

Pharmaceutical Sciences Faculty Patents

A method is described for the identification o f multi-subunit biocomplex drug targets. The method includes identifying a target that performs a biological function, wherein the target comprises one or more subunits, wherein a minimum number of the one or more subunits is inactivated to inhibit the biological function. The method includes selecting a drug that binds specifically to each subunit of the one or more subunits with a target probability. The method describes a relationship between inhibition efficiency of the drug and total number of the one or more subunits using a binomial distribution, wherein the inhibition efficiency comprises …

Dna Repair Pathways In Cancer Therapy And Resistance, Lan-Ya Li, Yi-Di Guan, Xi-Sha Chen, Jin-Ming Yang, Yan Cheng

Toxicology and Cancer Biology Faculty Publications

DNA repair pathways are triggered to maintain genetic stability and integrity when mammalian cells are exposed to endogenous or exogenous DNA-damaging agents. The deregulation of DNA repair pathways is associated with the initiation and progression of cancer. As the primary anti-cancer therapies, ionizing radiation and chemotherapeutic agents induce cell death by directly or indirectly causing DNA damage, dysregulation of the DNA damage response may contribute to hypersensitivity or resistance of cancer cells to genotoxic agents and targeting DNA repair pathway can increase the tumor sensitivity to cancer therapies. Therefore, targeting DNA repair pathways may be a potential therapeutic approach for …

The Inhibition Of Cdk8/19 Mediator Kinases Prevents The Development Of Resistance To Egfr-Targeting Drugs, Amanda C. Sharko, Chang-Uk Lim, Martina S.J. Mcdermott, Chuck Hennes, Kingsavanh P. Philavong, Tiffanie Aiken, Victor V. Tatarskiy, Igor Roninson Ph. D., Eugenia Broude

Faculty Publications

Drug resistance is the main obstacle to achieving cures with both conventional and targeted anticancer drugs. The emergence of acquired drug resistance is initially mediated by non-genetic transcriptional changes, which occur at a much higher frequency than mutations and may involve population-scale transcriptomic adaptation. CDK8/19 kinases, through association with transcriptional Mediator complex, regulate transcriptional reprogramming by co-operating with different signal-responsive transcription factors. Here we tested if CDK8/19 inhibition could prevent adaptation to drugs acting on epidermal growth factor receptor (EGFR/ERBB1/HER1). The development of resistance was analyzed following long-term exposure of BT474 and SKBR3 breast cancer cells to EGFR-targeting small molecules …

Novel Small Molecule Antifungals For Invasive Fungal Infections, Emily Dennis

Theses and Dissertations--Pharmacy

Human fungal pathogens cause a range of diseases from benign skin conditions (i.e., ringworm) to thrush, mucosal membrane infections, and life-threatening systemic infections including bloodstream infections (i.e., aspergillosis and candidiasis) and Cryptococcal meningitis. These systemic infections occur most often in immunocompromised individuals and have high mortality rates. Current antifungal agents used in the clinic belong to three main classes: the polyenes (e.g., amphotericin B (AmB)), the echinocandins (e.g., caspofungin (CFG)), and the azoles (e.g., fluconazole (FLC)). In addition, the antimetabolite pyrimidine analogue flucytosine is used in combination with AmB. The …

A Multifaceted Approach To Antibiotic Stewardship In The Outpatient Clinical Setting For Bronchitis, Elizabeth A. Weaver

Evidence-Based Practice Project Reports

Antimicrobial resistance is a world-wide health crisis (Infectious Disease Society of America [IDSA], 2016; World Health Organization [WHO], 2017) expedited by the overuse/inappropriate use of antibiotics. In the outpatient setting it has been determined that approximately 60% of antibiotic therapies are prescribed (Centers for Disease Control and Prevention [CDC], 2016). Antibiotic stewardship is the coordinated effort to improve the use of antibiotic therapies, minimize misdiagnosis and delayed diagnosis and select appropriate antibiotic drug regimens (IDSA, 2016). The purpose of this evidence-based practice project was to evaluate the effects of an antibiotic stewardship program (presentation, survey collection, bimonthly e-mail reminders, patient …

Interdependence Of Inhibitor Recognition In Hiv-1 Protease, Janet L. Paulsen, Florian Leidner, Debra A. Ragland, Nese Kurt Yilmaz, Celia A. Schiffer

Celia A. Schiffer

Molecular recognition is a highly interdependent process. Subsite couplings within the active site of proteases are most often revealed through conditional amino acid preferences in substrate recognition. However, the potential effect of these couplings on inhibition and thus inhibitor design is largely unexplored. The present study examines the interdependency of subsites in HIV-1 protease using a focused library of protease inhibitors, to aid in future inhibitor design. Previously a series of darunavir (DRV) analogs was designed to systematically probe the S1' and S2' subsites. Co-crystal structures of these analogs with HIV-1 protease provide the ideal opportunity to probe subsite interdependency. …

Chemosensitization Effect Of Sp1017 On Multiple Myeloma, Hangting Hu

Theses & Dissertations

Multiple myeloma (MM) is a hematological malignancy of plasma cells that are predominantly located in bone marrow (BM). Despite recent improvements in MM treatment by introduction of several novel agents includingimmunomodulatory drugs, proteasome inhibitors and the use of the drug combinations, MM remains incurable and almost all patients eventually relapse or become refractory to the current treatment regimens. So the current challenge of MM treatments is to maintain treatment response, prevent relapse and eventually prolong survival.

Here we demonstrated that Pluronic block copolymers ((Pluronic L61: Pluronic F127 = 1:8 w/w, SP1017) significantly increase cytotoxicity of proteasome inhibitors (Bortezomib, BTZ or …

Haemophilus Influenzae Responds To Glucocorticoids Used In Asthma Therapy By Modulation Of Biofilm Formation And Antibiotic Resistance, Chris S. Earl, Tee Wooi Keong, Shi-Qi An, Sarah Murdoch, Yvonne Mccarthy, Junkal Garmendia, Joseph Ward, J Maxwell Dow, Liang Yang, George A. O'Toole, Robert P. Ryan

Dartmouth Scholarship

Glucocorticosteroids are used as a main treatment to reduce airway inflammation in people with asthma who suffer from neutrophilic airway inflammation, a condition frequently associ- ated with Haemophilus influenzae colonization. Here we show that glucocorticosteroids have a direct influence on the behavior of H. influenzae that may account for associated difficulties with therapy. Using a mouse model of infection, we show that cortico- steroid treatment promotes H. influenzae persistence. Transcrip- tomic analysis of bacteria either isolated from infected mouse airway or grown in laboratory medium identified a number of genes encoding regulatory factors whose expression responded to the presence of …

Combination Of Sirna-Directed Gene Silencing With Cisplatin Reverses Drug Resistance In Human Non-Small Cell Lung Cancer, Shanthi Ganesh, Arun K. Iyer, Jan Weller, David V. Morrissey, Mansoor M. Amiji

Pharmaceutical Sciences Faculty Publications

One of the most challenging aspects of lung cancer therapy is the rapid acquisition of multidrug-resistant (MDR) phenotype. One effective approach would be to identify and downregulate resistance-causing genes in tumors using small interfering RNAs (siRNAs) to increase the sensitivity of tumor cells to chemotherapeutic challenge. After identifying the overexpressed resistance-related antiapoptotic genes (survivin and bcl-2) in cisplatin-resistant cells, the siRNA sequences were designed and screened to select the most efficacious candidates. Modifications were introduced in them to minimize off-target effects. Subsequently, the combination of siRNA and cisplatin that gave the maximum synergy was identified in resistant cells. We then …

Doxorubicin Loaded Polymeric Nanoparticulate Delivery System To Overcome Drug Resistance In Osteosarcoma, Michiro Susa, Arun K. Iyer, Keinosuke Ryu, Francis John Hornicek, Henry J. Mankin, Mansoor M. Amiji, Zhenfeng Duan

Arun Iyer

Background: Drug resistance is a primary hindrance for the efficiency of chemotherapy against osteosarcoma. Although chemotherapy has improved the prognosis of osteosarcoma patients dramatically after introduction of neo-adjuvant therapy in the early 1980's, the outcome has since reached plateau at approximately 70% for 5 year survival. The remaining 30% of the patients eventually develop resistance to multiple types of chemotherapy. In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure incurred from multidrug resistant (MDR) tumor cells, we explored the possibility of loading doxorubicin onto biocompatible, lipid-modified dextran-based polymeric nanoparticles and evaluated the …

Inhibition Of Abcb1 (Mdr1) Expression By An Sirna Nanoparticulate Delivery System To Overcome Drug Resistance In Osteosarcoma, Michiro Susa, Arun Iyer, Keinosuke Ryu, Edwin Choi, Francis Hornicek, Henry Mankin, Lara Milane, Mansoor Amiji, Zhenfeng Duan

Arun Iyer

Background: The use of neo-adjuvant chemotherapy in treating osteosarcoma has improved patients’ average 5 year survival rate from 20% to 70% in the past 30 years. However, for patients who progress after chemotherapy, its effectiveness diminishes due to the emergence of multi-drug resistance (MDR) after prolonged therapy. Methodology/Principal Findings: In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure resulting from MDR, we designed and evaluated a novel drug delivery system for MDR1 siRNA delivery. Novel biocompatible, lipid-modified dextran-based polymeric nanoparticles were used as the platform for MDR1 siRNA delivery; and the efficacy …

The Challenge Of Developing Robust Drugs To Overcome Resistance, Celia Schiffer, Amy C. Anderson, Michael P. Pollastri, Norton P. Peet

Michael Pollastri

Drug resistance is problematic in microbial disease, viral disease and cancer. Understanding at the outset that resistance will impact the effectiveness of any new drug that is developed for these disease categories is imperative. In this Perspective, we detail approaches that have been taken with selected drug targets to reduce the susceptibility of new drugs to resistance mechanisms. We will also define the concepts of robust drugs and resilient targets, and discuss how the design of robust drugs and the selection of resilient targets may lead to successful strategies for combating resistance.

Doxorubicin Loaded Polymeric Nanoparticulate Delivery System To Overcome Drug Resistance In Osteosarcoma, Michiro Susa, Arun K. Iyer, Keinosuke Ryu, Francis John Hornicek, Henry J. Mankin, Mansoor M. Amiji, Zhenfeng Duan

Mansoor M. Amiji

Background: Drug resistance is a primary hindrance for the efficiency of chemotherapy against osteosarcoma. Although chemotherapy has improved the prognosis of osteosarcoma patients dramatically after introduction of neo-adjuvant therapy in the early 1980's, the outcome has since reached plateau at approximately 70% for 5 year survival. The remaining 30% of the patients eventually develop resistance to multiple types of chemotherapy. In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure incurred from multidrug resistant (MDR) tumor cells, we explored the possibility of loading doxorubicin onto biocompatible, lipid-modified dextran-based polymeric nanoparticles and evaluated the …

Inhibition Of Abcb1 (Mdr1) Expression By An Sirna Nanoparticulate Delivery System To Overcome Drug Resistance In Osteosarcoma, Michiro Susa, Arun K. Iyer, Keinosuke Ryu, Edwin Choi, Francis John Hornicek, Henry J. Mankin, Lara Milane, Mansoor M. Amiji, Zhenfeng Duan

Mansoor M. Amiji

Background: The use of neo-adjuvant chemotherapy in treating osteosarcoma has improved patients’ average 5 year survival rate from 20% to 70% in the past 30 years. However, for patients who progress after chemotherapy, its effectiveness diminishes due to the emergence of multi-drug resistance (MDR) after prolonged therapy. Methodology/Principal Findings: In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure resulting from MDR, we designed and evaluated a novel drug delivery system for MDR1 siRNA delivery. Novel biocompatible, lipid-modified dextran-based polymeric nanoparticles were used as the platform for MDR1 siRNA delivery; and the efficacy …

Inhibition Of Abcb1 (Mdr1) Expression By An Sirna Nanoparticulate Delivery System To Overcome Drug Resistance In Osteosarcoma, Michiro Susa, Arun K. Iyer, Keinosuke Ryu, Edwin Choy, Francis J. Hornicek, Henry Mankin, Lara Milane, Mansoor M. Amiji, Zhenfeng Duan

Pharmaceutical Sciences Faculty Publications

Background: The use of neo-adjuvant chemotherapy in treating osteosarcoma has improved patients’ average 5 year survival rate from 20% to 70% in the past 30 years. However, for patients who progress after chemotherapy, its effectiveness diminishes due to the emergence of multi-drug resistance (MDR) after prolonged therapy.

Methodology/Principal Findings: In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure resulting from MDR, we designed and evaluated a novel drug delivery system for MDR1 siRNA delivery. Novel biocompatible, lipid-modified dextran-based polymeric nanoparticles were used as the platform for MDR1 siRNA delivery; and the efficacy …

Doxorubicin Loaded Polymeric Nanoparticulate Delivery System To Overcome Drug Resistance In Osteosarcoma, Michiro Susa, Arun K. Iyer, Keinosuke Ryu, Francis J. Hornicek, Henry Mankin, Mansoor M. Amiji, Zhenfeng Duan

Pharmaceutical Sciences Faculty Publications

Background: Drug resistance is a primary hindrance for the efficiency of chemotherapy against osteosarcoma. Although chemotherapy has improved the prognosis of osteosarcoma patients dramatically after introduction of neo-adjuvant therapy in the early 1980's, the outcome has since reached plateau at approximately 70% for 5 year survival. The remaining 30% of the patients eventually develop resistance to multiple types of chemotherapy. In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure incurred from multidrug resistant (MDR) tumor cells, we explored the possibility of loading doxorubicin onto biocompatible, lipid-modified dextran-based polymeric nanoparticles and evaluated the …

Design, Synthesis, And Evaluation Of 10-N-Substituted Acridones As Novel Chemosensitizers In Plasmodium Falciparum, Jane X. Kelly, Martin J. Smilkstein, Roland A. Cooper, Kristin D. Lane, Robert A. Johnson, Aaron Janowsky, Rozalia A. Dodean, David J. Hinrichs, Rolf Winter, Michael Riscoe

Biological Sciences Faculty Publications

A series of novel 10-N-substituted acridones, bearing alkyl side chains with tertiary amine groups at the terminal position, were designed, synthesized, and evaluated for the ability to enhance the potency of quinoline drugs against multidrug-resistant (MDR) Plasmodium falciparum malaria parasites. A number of acridone derivatives, with side chains bridged three or more carbon atoms apart between the ring nitrogen and terminal nitrogen, demonstrated chloroquine (CQ)-chemosensitizing activity against the MDR strain of P. falciparum (Dd2). Isobolograrn analysis revealed that selected candidates demonstrated significant synergy with CQ in the CQ-resistant (CQR) parasite Dd2 but only additive (or indifferent) interaction in the CQ-sensitive …

Allelic Modifications Of The Cg2 And Cg1 Genes Do Not Alter The Chloroquine Response Of Drug-Resistant Plasmodium Falciparum, David A. Fidock, Takashi Nomura, Roland A. Cooper, Xin-Zhuan Su, Angela K. Talley, Thomas E. Wellems

Roland A. Cooper