Kenneth D. Tew | |
---|---|
Born | |
Occupation(s) | Pharmacologist, academic and author |
Spouse | Danyelle Townsend |
Academic background | |
Education | BSc., Microbiology/Genetics PhD., Biochemical Pharmacology DSc |
Alma mater | University of Wales, Swansea University of London |
Academic work | |
Institutions | Medical University of South Carolina |
Kenneth D. Tew is a Scottish-American pharmacologist,academic and author. He is a professor in the Department of Cell &Molecular Pharmacology and the John C. West Endowed Chair in Cancer Research at the Medical University of South Carolina. [1]
Tew's research primarily focuses on identifying cancer strategies with strong translational potential,particularly in the context of redox pathways,and resistance to various drugs to understand redox mechanisms and their connections to essential signaling pathways. [2] He has authored,co-authored and edited research articles and books such as Preclinical and Clinical Modulation of Anticancer Drugs and Basic Science of Cancer. He is the recipient of the Outstanding Investigator Grant from the National Cancer Institute in 1993,the 2003 American Cancer Society Scientific Research Award and the 2010 Astellas USA Foundation Award from the American Society for Pharmacology and Experimental Therapeutics. [3]
Tew is an Elected Fellow of the American Association for the Advancement of Science [4] and the American Society for Pharmacology and Experimental Therapeutics. [5] He is an Executive Editor of Biomedicine &Pharmacotherapy . [6]
Tew earned a Bachelor of Science in Microbiology/Genetics from the University of Wales,Swansea in 1973 and a PhD in Biochemical Pharmacology from the University of London,where he also received postdoctoral training in 1976. He served as the Head of the Basic Pharmacology Program at the Lombardi Cancer Center from 1982 to 1985,when he became a member and later Chairman of Pharmacology at the Fox Chase Cancer Center. Concurrently,he worked as an Adjunct Associate Professor of Pharmacology at the University of Pennsylvania until 1990 and was awarded his DSc from the University of London in 1995. [7]
Tew was appointed the G. Willing Chair in Cancer Research at the Medical University of South Carolina from 1999 to 2004. He was the Director of the Developmental Cancer Therapeutics Program at Hollings Cancer Center from 2004 to 2019,and serves as a professor in the Department of Cell &Molecular Pharmacology at the Medical University of South Carolina. [1]
Tew has been the John C. West Chair in Cancer Research at the Medical University of South Carolina since 2004. [8]
Tew held the position of Associate Editor from 1993 to 2007 and later assumed the role of Senior Editor in the Experimental Therapeutics,Molecular Targets,and Chemical Biology Section from 2007 to 2018 for the journal Cancer Research . Concurrently,he held editorial positions including,Editor for Cellular Pharmacology,and Editor-in-Chief of Journal of Pharmacology and Experimental Therapeutics . [7]
Tew has been the Editor (USA) of Biomedicine &Pharmacotherapy since 2002 [6] and Serial Editor for Advances in Cancer Research since 2011. [9] Additionally,he has held appointments at InVaMet Therapeutics and the Greehey Children's Cancer Research Institute Scientific External Advisory Board since 2019. [10]
Through his research laboratory,the Tew laboratory,he has conducted research in redox pathways,with an emphasis on drug development,biomarker identification,and comprehending the effects of reactive oxygen and nitrogen species on cancer cells. [2] [11] He has focused on distinct post-translationally modified S-glutathionylated proteins affecting cell-signaling pathways,potentially acting as surrogate plasma biomarkers for drug response induced by oxidative and nitrosative stress. He holds patents for his work,contributing to the development of a glutathione S-transferase-activated prodrug and two small molecules in clinical development as potential myeloproliferative agents. [12]
Tew has co-authored 2 books focusing on carcinogenesis and cancer treatment strategies. He co-wrote Preclinical and Clinical Modulation of Anticancer Drugs with Peter J. Houghton and Janet A. Houghton,providing an analysis of theoretical and practical approaches to the design and implementation of modulation principles. His collaborative work with Gary D. Kruh,Basic Science of Cancer,explored the advancements in cancer research,covering interrelated topics such as tumor suppressor genes,apoptosis,transcriptional regulation,pharmacology of anticancer drugs,cytogenetic techniques,oncogenes,and signal transductions. [13]
Tew co-edited books from the series Advances in Cancer Research alongside Paul B. Fisher,where they provided reviews on diverse cancer research topics. In a review published in the Journal of Medicinal Chemistry ,Thomas J. Bardos wrote about the series,"This rapidly growing series of volumes containing many excellent,highly informative,in-depth reviews on a variety of timely topics relating to cancer research has always been most representative in the areas of tumor biology and immunology." [14]
Tew's work on redox and pharmacogenetics focused on the discovery and development of drugs. Alongside colleagues,he introduced a novel zebrafish model with a glutathione S-transferase π1 (gstp1) knockout,revealing insights into redox homeostasis,reductive stress,and responses to drugs inducing endoplasmic reticulum stress and the unfolded protein response. [15] [16] His research has looked into the role of GTSP in cellular redox homeostasis and its over-expression in cancer drug resistance,particularly in the context of preclinical and clinical testing of the GSTP inhibitor TLK199 (Telintra) for treating myelodysplastic syndrome. [17] He further revealed that the absence of microsomal glutathione transferase 1 (MGST1) impacts melanin biosynthesis and melanoma growth in mice and that,in numerous species,members of the GST family are involved in early hematopoiesis, [18] and that the lack of GSTP in dendritic cells leads to increased proliferation,ROS levels and ERαlevels,suggesting a role for GSTP in controlling ERαactivity and dendritic cell function. [19]
Additionally,Tew and colleagues investigated how S-glutathionylation of the protein BiP,mediated by GSTP,contributes to acquired resistance to the multiple myeloma treatment bortezomib (Btz) by impacting BiP's foldase and ATPase activities. [20] In another collaborative study published in Scientific Reports,he found that S-glutathionylated serpins,specifically A1 and A3,are elevated in the blood of prostate cancer patients after radiation therapy,suggesting their potential as biomarkers for radiation exposure. [21] He also explored melanoma cell lines resistant to reductive stress agents,showcasing changes in cell and mitochondrial morphology,metabolic preferences,and adaptive mechanisms in lethal reductive stress conditions. [22]
Tew has studied cancer strategies to devise new treatments. In a joint research,he highlighted the significance of microsomal glutathione transferase 1 (MGST1) in melanin biosynthetic pathways,revealing its role as a determinant of tumor progression,with MGST1 knockdown leading to depigmentation,increased oxidative stress,and hindered tumor growth. [23] He also determined that inhibiting microsomal glutathione S-transferase 1 (MGST1) in melanoma enhances oxidative stress,increases sensitivity to anticancer drugs,and reduces metastasis,improving the effectiveness of therapies. [24]
Tew examined ME-344,a second-generation isoflavone with anticancer properties in 2019,demonstrating its impact on redox homeostasis,mitochondrial function,and specific targeting of heme oxygenase 1 (HO-1) in lung cancer cells. [25] In 2020,he determined that ME-344 targets VDAC1 and VDAC2 in lung cancer cells,leading to ROS generation,Bax translocation,cytochrome c release,and apoptosis,highlighting their potential as therapeutic targets. [26] He also assessed how reactive oxygen species (ROS) play a dual role in cancer evolution,influencing both tumorigenesis and cell death,and highlighted tumor cell adaptations in metabolism and antioxidant defenses to manage ROS levels during different stages of cancer development. [27]
Glutathione is an organic compound with the chemical formula HOCOCH(NH2)CH2CH2CONHCH(CH2SH)CONHCH2COOH. It is an antioxidant in plants,animals,fungi,and some bacteria and archaea. Glutathione is capable of preventing damage to important cellular components caused by sources such as reactive oxygen species,free radicals,peroxides,lipid peroxides,and heavy metals. It is a tripeptide with a gamma peptide linkage between the carboxyl group of the glutamate side chain and cysteine. The carboxyl group of the cysteine residue is attached by normal peptide linkage to glycine.
Drug metabolism is the metabolic breakdown of drugs by living organisms,usually through specialized enzymatic systems. More generally,xenobiotic metabolism is the set of metabolic pathways that modify the chemical structure of xenobiotics,which are compounds foreign to an organism's normal biochemistry,such as any drug or poison. These pathways are a form of biotransformation present in all major groups of organisms and are considered to be of ancient origin. These reactions often act to detoxify poisonous compounds. The study of drug metabolism is called pharmacokinetics.
4-Hydroxynonenal,or 4-hydroxy-2E-nonenal or 4-hydroxy-2-nonenal or 4-HNE or HNE,,is an α,β-unsaturated hydroxyalkenal that is produced by lipid peroxidation in cells. 4-HNE is the primary α,β-unsaturated hydroxyalkenal formed in this process. It is a colorless oil. It is found throughout animal tissues,and in higher quantities during oxidative stress due to the increase in the lipid peroxidation chain reaction,due to the increase in stress events. 4-HNE has been hypothesized to play a key role in cell signal transduction,in a variety of pathways from cell cycle events to cellular adhesion.
Glutathione S-transferases (GSTs),previously known as ligandins,are a family of eukaryotic and prokaryotic phase II metabolic isozymes best known for their ability to catalyze the conjugation of the reduced form of glutathione (GSH) to xenobiotic substrates for the purpose of detoxification. The GST family consists of three superfamilies:the cytosolic,mitochondrial,and microsomal—also known as MAPEG—proteins. Members of the GST superfamily are extremely diverse in amino acid sequence,and a large fraction of the sequences deposited in public databases are of unknown function. The Enzyme Function Initiative (EFI) is using GSTs as a model superfamily to identify new GST functions.
Chlorambucil,sold under the brand name Leukeran among others,is a chemotherapy medication used to treat chronic lymphocytic leukemia (CLL),Hodgkin lymphoma,and non-Hodgkin lymphoma. For CLL it is a preferred treatment. It is given by mouth.
Redox therapy is an experimental therapy that aims to effect an outcome by modifying the levels of pro-oxidant and antioxidant agents in cells. The term "redox" is a contraction of "reduction-oxidation". For cancer patients,the therapy is predicated on the idea that the redox state of cells may have an effect on cancer development.
Glutathione S-transferase P is an enzyme that in humans is encoded by the GSTP1 gene.
Nuclear factor erythroid 2-related factor 2 (NRF2),also known as nuclear factor erythroid-derived 2-like 2,is a transcription factor that in humans is encoded by the NFE2L2 gene. NRF2 is a basic leucine zipper (bZIP) protein that may regulate the expression of antioxidant proteins that protect against oxidative damage triggered by injury and inflammation,according to preliminary research. In vitro,NRF2 binds to antioxidant response elements (AREs) in the promoter regions of genes encoding cytoprotective proteins. NRF2 induces the expression of heme oxygenase 1 in vitro leading to an increase in phase II enzymes. NRF2 also inhibits the NLRP3 inflammasome.
Microsomal glutathione S-transferase 1 is an enzyme that in humans is encoded by the MGST1 gene.
Cystine/glutamate transporter is an antiporter that in humans is encoded by the SLC7A11 gene.
The alpha-7 nicotinic receptor,also known as the α7 receptor,is a type of nicotinic acetylcholine receptor implicated in long-term memory,consisting entirely of α7 subunits. As with other nicotinic acetylcholine receptors,functional α7 receptors are pentameric [i.e.,(α7)5 stoichiometry].
Glutathione S-transferase kappa 1 (GSTK1) is an enzyme that in humans is encoded by the GSTK1 gene which is located on chromosome seven. It belongs to the superfamily of enzymes known as glutathione S-transferase (GST),which are mainly known for cellular detoxification. The GSTK1 gene consists of eight exons and seven introns and although it is a member of the GST family,its structure has been found to be similar to bacterial HCCA (2-hydroxychromene-2-carboxylate) isomerases and bacterial disulphide-bond-forming DsbA oxidoreductase. This similarity has later allowed the enzyme GSTK1 to be renamed to DsbA-L. Research has also suggested that several variations of the GSTK1 gene can be responsible for metabolic diseases and certain types of cancer.
Ro60-0175 is a drug developed by Hoffmann–La Roche,which has applications in scientific research. It acts as a potent and selective agonist for both the 5-HT2B and 5-HT2C serotonin receptor subtypes,with good selectivity over the closely related 5-HT2A subtype,and little or no affinity at other receptors.
The alpha-3 beta-4 nicotinic receptor,also known as the α3β4 receptor and the ganglion-type nicotinic receptor,is a type of nicotinic acetylcholine receptor,consisting of α3 and β4 subunits. It is located in the autonomic ganglia and adrenal medulla,where activation yields post- and/or presynaptic excitation,mainly by increased Na+ and K+ permeability.
Ruthenium anti-cancer drugs are coordination complexes of ruthenium complexes that have anticancer properties. They promise to provide alternatives to platinum-based drugs for anticancer therapy. No ruthenium anti-cancer drug has been commercialized.
Reductive stress (RS) is defined as an abnormal accumulation of reducing equivalents despite being in the presence of intact oxidation and reduction systems. A redox reaction involves the transfer of electrons from reducing agents (reductants) to oxidizing agents (oxidants) and redox couples are accountable for the majority of the cellular electron flow. RS is a state where there are more reducing equivalents compared to reductive oxygen species (ROS) in the form of known biological redox couples such as GSH/GSSG,NADP+/NADPH,and NAD+/NADH. Reductive stress is the counterpart to oxidative stress,where electron acceptors are expected to be mostly reduced. Reductive stress is likely derived from intrinsic signals that allow for the cellular defense against pro-oxidative conditions. There is a feedback regulation balance between reductive and oxidative stress where chronic RS induce oxidative species (OS),resulting in an increase in production of RS,again.
Conventional drug delivery is limited by the inability to control dosing,target specific sites,and achieve targeted permeability. Traditional methods of delivering therapeutics to the body experience challenges in achieving and maintaining maximum therapeutic effect while avoiding the effects of drug toxicity. Many drugs that are delivered orally or parenterally do not include mechanisms for sustained release,and as a result they require higher and more frequent dosing to achieve any therapeutic effect for the patient. As a result,the field of drug delivery systems developed into a large focus area for pharmaceutical research to address these limitations and improve quality of care for patients. Within the broad field of drug delivery,the development of stimuli-responsive drug delivery systems has created the ability to tune drug delivery systems to achieve more controlled dosing and targeted specificity based on material response to exogenous and endogenous stimuli.
Reduction-sensitive nanoparticles (RSNP) consist of nanocarriers that are chemically responsive to reduction. Drug delivery systems using RSNP can be loaded with different drugs that are designed to be released within a concentrated reducing environment,such as the tumor-targeted microenvironment. Reduction-Sensitive Nanoparticles provide an efficient method of targeted drug delivery for the improved controlled release of medication within localized areas of the body.
Famitinib is a tyrosine kinase receptor inhibitor developed by Jiangsu Hengrui for a variety of cancers.
Danyelle M. Townsend is a biomedical scientist,and academic. She is a Professor and acting Department Chair of Drug Discovery and Biomedical Sciences at the Medical University of South Carolina (MUSC).