Abstract
Escherichia coli purine nucleoside phosphorylase (PNP) catalyzes the cleavage of 9-(2-deoxy-β-Dribofuranosyl)- 6-methylpurine (MeP-dR), while human PNP does not. MeP-dR is well tolerated while the cleavage product, 6-methylpurine (MeP), is highly cytotoxic. This clinical profile suggests an anticancer gene therapy strategy in which solid tumors are transfected with the gene for E. coli PNP. Tumor cells expressing E. coli PNP will liberate MeP and be killed. Furthermore, MeP released from the cell via the purine transport system will enter nearby cells, resulting in bystander killing of tumor cells. To reduce toxicity resulting from activation of MeP-dR by intestinal tract flora, we redesigned the E. coli PNP active site to cleave prodrugs that are not cleaved by wild type E. coli PNP. It is possible that the variation of substrate specificity among enzymes that cleave nucleosides will have broader application in the gene therapy approach to prodrug activation. Here we review progress in the development of E. coli PNP anticancer gene therapy. We also review the structural basis for activity of nucleoside phosphorylases and suggest future directions for the development of activating enzymes for suicide gene therapy.
Keywords: activating enzyme, prodrug, cancer, suicide gene therapy, protein redesign, 6-methylpurine, glycosidic bond, bystander killing
Current Topics in Medicinal Chemistry
Title: PNP Anticancer Gene Therapy
Volume: 5 Issue: 13
Author(s): Yang Zhang, William B. Parker, Eric J. Sorscher and Steven E. Ealick
Affiliation:
Keywords: activating enzyme, prodrug, cancer, suicide gene therapy, protein redesign, 6-methylpurine, glycosidic bond, bystander killing
Abstract: Escherichia coli purine nucleoside phosphorylase (PNP) catalyzes the cleavage of 9-(2-deoxy-β-Dribofuranosyl)- 6-methylpurine (MeP-dR), while human PNP does not. MeP-dR is well tolerated while the cleavage product, 6-methylpurine (MeP), is highly cytotoxic. This clinical profile suggests an anticancer gene therapy strategy in which solid tumors are transfected with the gene for E. coli PNP. Tumor cells expressing E. coli PNP will liberate MeP and be killed. Furthermore, MeP released from the cell via the purine transport system will enter nearby cells, resulting in bystander killing of tumor cells. To reduce toxicity resulting from activation of MeP-dR by intestinal tract flora, we redesigned the E. coli PNP active site to cleave prodrugs that are not cleaved by wild type E. coli PNP. It is possible that the variation of substrate specificity among enzymes that cleave nucleosides will have broader application in the gene therapy approach to prodrug activation. Here we review progress in the development of E. coli PNP anticancer gene therapy. We also review the structural basis for activity of nucleoside phosphorylases and suggest future directions for the development of activating enzymes for suicide gene therapy.
Export Options
About this article
Cite this article as:
Zhang Yang, Parker B. William, Sorscher J. Eric and Ealick E. Steven, PNP Anticancer Gene Therapy, Current Topics in Medicinal Chemistry 2005; 5 (13) . https://dx.doi.org/10.2174/156802605774463105
DOI https://dx.doi.org/10.2174/156802605774463105 |
Print ISSN 1568-0266 |
Publisher Name Bentham Science Publisher |
Online ISSN 1873-4294 |
Call for Papers in Thematic Issues
Chemistry Based on Natural Products for Therapeutic Purposes
The development of new pharmaceuticals for a wide range of medical conditions has long relied on the identification of promising natural products (NPs). There are over sixty percent of cancer, infectious illness, and CNS disease medications that include an NP pharmacophore, according to the Food and Drug Administration. Since NP ...read more
Current Trends in Drug Discovery Based on Artificial Intelligence and Computer-Aided Drug Design
Drug development discovery has faced several challenges over the years. In fact, the evolution of classical approaches to modern methods using computational methods, or Computer-Aided Drug Design (CADD), has shown promising and essential results in any drug discovery campaign. Among these methods, molecular docking is one of the most notable ...read more
Drug Discovery in the Age of Artificial Intelligence
In the age of artificial intelligence (AI), we have witnessed a significant boom in AI techniques for drug discovery. AI techniques are increasingly integrated and accelerating the drug discovery process. These developments have not only attracted the attention of academia and industry but also raised important questions regarding the selection ...read more
From Biodiversity to Chemical Diversity: Focus of Flavonoids
Flavonoids are the largest group of polyphenols, plant secondary metabolites arising from the essential aromatic amino acid phenylalanine (or more rarely from tyrosine) via the phenylpropanoid pathway. The flavan nucleus is the basic 15-carbon skeleton of flavonoids (C6-C3-C6), which consists of two phenyl rings (A and B) and a heterocyclic ...read more
- Author Guidelines
- Graphical Abstracts
- Fabricating and Stating False Information
- Research Misconduct
- Post Publication Discussions and Corrections
- Publishing Ethics and Rectitude
- Increase Visibility of Your Article
- Archiving Policies
- Peer Review Workflow
- Order Your Article Before Print
- Promote Your Article
- Manuscript Transfer Facility
- Editorial Policies
- Allegations from Whistleblowers
- Announcements
Related Articles
-
subject Index To Volume 2
Current Medicinal Chemistry - Immunology, Endocrine & Metabolic Agents Prostaglandin J2 Family and the Cardiovascular System
Current Vascular Pharmacology A Systems Biology Road Map for the Discovery of Drugs Targeting Cancer Cell Metabolism
Current Pharmaceutical Design Advances and Future Challenges in Adenoviral Vector Pharmacology and Targeting
Current Gene Therapy Bioconversion of Isoflavones into Bioactive Equol: State of the Art
Recent Patents on Food, Nutrition & Agriculture Neural Stem Cells - A Promising Potential Therapy for Brain Tumors
Current Stem Cell Research & Therapy Novel Phospholipid-Based Labrasol Nanomicelles Loaded Flavonoids for Oral Delivery with Enhanced Penetration and Anti-Brain Tumor Efficiency
Current Drug Delivery Imidazoquinolines: Recent Developments in Anticancer Activity
Mini-Reviews in Medicinal Chemistry Pharmaceutical Applications of Graphene-based Nanosheets
Current Pharmaceutical Biotechnology Stem Cell Differentiation Stage Factors from Zebrafish Embryo: A Novel Strategy to Modulate the Fate of Normal and Pathological Human (Stem) Cells
Current Pharmaceutical Biotechnology Natural Compounds with Proteasome Inhibitory Activity for Cancer Prevention and Treatment
Current Protein & Peptide Science p38 MAP Kinase Interacts with and Stabilizes Pancreatic and Duodenal Homeobox-1
Current Molecular Medicine Cell Death and Survival Through the Endoplasmic Reticulum- Mitochondrial Axis
Current Molecular Medicine Targeted Drug Delivery to Cancer Stem Cells through Nanotechnological Approaches
Current Stem Cell Research & Therapy Thalidomide Derived Immunomodulatory Drugs (IMiDs) as Potential Therapeutic Agents
Current Drug Targets - Immune, Endocrine & Metabolic Disorders Endogenous Regulators of Adult CNS Neurogenesis
Current Pharmaceutical Design Current HPLC Methods for Assay of Nano Drug Delivery Systems
Current Topics in Medicinal Chemistry Extracellular ATP and Neurodegeneration
Current Drug Targets - CNS & Neurological Disorders Exploration of (hetero)aryl Derived Thienylchalcones for Antiviral and Anticancer Activities
Medicinal Chemistry Different Treatment Strategies for Pediatric Brain Tumors
Current Pediatric Reviews