Carboxypeptidase G2-based gene-directed enzyme–prodrug therapy: a new weapon in the GDEPT armoury

2007 ◽  
Vol 7 (11) ◽  
pp. 870-879 ◽  
Author(s):  
Douglas Hedley ◽  
Lesley Ogilvie ◽  
Caroline Springer
Keyword(s):  
Enzyme Prodrug Therapy ◽  
Carboxypeptidase G2

scholarly journals Coupling of a Novel TIMP3 Peptide to Carboxypeptidase G2 for Pro-Drug Activation at the Tumour Site

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 625
Author(s):  
Mohammed S. Aldughaim ◽  
Fatimah Alsaffar ◽  
Michael D. Barker
Keyword(s):  
Fold Increase ◽  
Repeated Administration ◽  
Cytotoxic Drugs ◽  
Peptide Sequence ◽  
Tumour Site ◽  
Enzyme Prodrug Therapy ◽  
Nickel Affinity Chromatography ◽  
Glutamic Acid Residue ◽  
Carboxypeptidase G2 ◽  
Effective Delivery

Broad-spectrum cytotoxic drugs have been used in cancer therapy for decades. However, their lack of specificity to cancer cells often results in serious side-effects, limiting efficacy. For this reason, antibodies have been used to attempt to specifically target cytotoxic drugs to tumours. One such approach is antibody-directed enzyme prodrug therapy (ADEPT) which uses a tumour-directed monoclonal antibody, coupled to an enzyme, to convert a systemically administered non-toxic prodrug into a toxic one only at the tumour site. Among the main drawbacks of ADEPT is the immunogenicity of the antibody-enzyme complex, which is exacerbated by slow clearance due to size, hence limiting repeated administration. Additionally, the mono-specificity of the antibody could potentially result in drug resistance with repeated administration. We have identified a novel short peptide sequence, p700, derived from a human tissue inhibitor of metalloproteinases-3 (TIMP-3), which binds to and inhibits a number of tyrosine kinase growth factor receptors (VEGFRs1-3, FGFRs 1-4 and PDGFRα) which are known to be upregulated in many tumours and tumour vasculature. In this report, we fused p700 to His-tagged, codon-optimised, carboxypeptidase G2 (CPG2). CPG2 is a bacterial enzyme used in ADEPT, which activates potent nitrogen-mustard pro-drugs by removal of an inhibitory glutamic acid residue. Recombinant CPG2-p700 was highly expressed in Escherichia coli and successfully purified by nickel affinity chromatography. Biolayer interferometry showed that CPG2-p700 had a 100-fold increase in binding affinity for VEGFR2 compared with CPG2 alone and retained its catalytic activity, as determined by methotrexate cleavage. In the presence of CPG2-p700, the ZD2676P pro-drug showed significant cytotoxicity for 4T1 cells compared with prodrug alone or CPG2 alone. p700 is, therefore, a potentially useful alternative to monoclonal antibodies for enzyme pro-drug therapy and could equally be used for effective delivery of other cytotoxic drugs to tumour tissue.

scholarly journals Application of Gene-Directed Enzyme Prodrug Therapy in Cancer Treatment

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Cindy Yeoh Shin Ly ◽  
Anil Philip Kunnath
Keyword(s):  
Tumor Cells ◽  
Tumor Regression ◽  
Cytosine Deaminase ◽  
Therapeutic Index ◽  
Specific Gene ◽  
Enzyme Prodrug Therapy ◽  
E Coli ◽  
Carboxypeptidase G2 ◽  
High Concentrations ◽  
Simplex Virus

Gene-directed enzyme prodrug therapy (GDEPT) is an advanced cancer therapy that has potential use against localized and metastasized cancer. This strategy aims to improve the limitations of chemotherapy and existing cancer treatments by specific gene delivery, which allows the conversion of systemically administered nontoxic prodrugs to active chemotherapeutic drugs inside the target tumor cells, thereby resulting in a significant therapeutic index by introducing high concentrations of cytotoxic compounds to the tumor cells while limiting the systemic toxicity. The main attraction of GDEPT is by expanding the toxicity to adjacent non-expressing target cancer cells through local and distal bystander effects, leading to tumor regression. This review focused on the application of the six main GDEPT systems for treating cancer, including herpes simplex virus thymidine kinase (HSV-TK) with ganciclovir (GCV), cytosine deaminase (CD) from bacteria or yeast with 5-fluorocytosine (5-FC), E. coli nitroreductase (NfsB) with 5-(aziridin-1-yl)-2,4- initrobenzamide (CB1954), hepatic cytochrome P4l50 (CYP450) with cyclophosphamide (CPA), purine nucleoside phosphorylase (PNP) from E. coli with 6-methylpurine deoxyriboside (MEP), and bacterial carboxypeptidase G2 (CPG2) with 4-[(2-chloroethyl)(2-mesloxyethyl)amino] benzoyl-L-glutamic acid (CMDA). In each system, the mechanism of action, clinical trials for the past decades, limitations, and areas that need improvement are discussed.

Novel Inhibitors of Carboxypeptidase G2(CPG2):  Potential Use in Antibody-Directed Enzyme Prodrug Therapy

1999 ◽  
Vol 42 (6) ◽  
pp. 951-956 ◽  
Author(s):  
Tariq H. Khan ◽  
Ebun A. Eno-Amooquaye ◽  
Frances Searle ◽  
Pat J. Browne ◽  
Helen M. I. Osborn ◽  
...  
Keyword(s):  
Enzyme Prodrug Therapy ◽  
Carboxypeptidase G2 ◽  
Potential Use

scholarly journals Clinical Applications of Phage-Derived sFvs and sFv Fusion Proteins

2000 ◽  
Vol 16 (1-2) ◽  
pp. 53-62 ◽  
Author(s):  
K. A. Chester ◽  
J. Bhatia ◽  
G. Boxer ◽  
S. P. Cooke ◽  
A. A. Flynn ◽  
...  
Keyword(s):  
Fusion Proteins ◽  
Gamma Camera ◽  
Single Chain ◽  
Enzyme Prodrug Therapy ◽  
Radioimmunoguided Surgery ◽  
Patients With Cancer ◽  
Carboxypeptidase G2 ◽  
Single Chain Fv ◽  
Surgery Trial ◽  
Colorectal Adenocarcinomas

Single chain Fv antibodies (sFvs) have been produced from filamentous bacteriophage libraries obtained from immunised mice. MFE-23, the most characterised of these sFvs, is reactive with carcinoembryonic antigen (CEA), a glycoprotein that is highly expressed in colorectal adenocarcinomas. MFE-23 has been expressed in bacteria and purified in our laboratory for two clinical trials; a gamma camera imaging trial using123I-MFE-23 and a radioimmunoguided surgery trial using125I-MFE-23, where tumour deposits are detected by a hand-held probe during surgery. Both these trials show MFE-23 is safe and effective in localising tumour deposits in patients with cancer. We are now developing fusion proteins which use MFE-23 to deliver a therapeutic moiety; MFE-23::CPG2 targets the enzyme carboxypeptidase G2 (CPG2) for use in the ADEPT (antibody directed enzyme prodrug therapy) system and MFE::TNFα aims to reduce sequestration and increase tumor concentrations of systemically administered TNFα.

scholarly journals Systemic Gene-Directed Enzyme Prodrug Therapy of Hepatocellular Carcinoma Using a Targeted Adenovirus Armed with Carboxypeptidase G2

2005 ◽  
Vol 65 (12) ◽  
pp. 5003-5008 ◽  
Author(s):  
Silke Schepelmann ◽  
Paul Hallenbeck ◽  
Lesley M. Ogilvie ◽  
Douglas Hedley ◽  
Frank Friedlos ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Enzyme Prodrug Therapy ◽  
Carboxypeptidase G2

Novel Fluorinated Prodrugs for Activation by Carboxypeptidase G2 Showing Good in Vivo Antitumor Activity in Gene-Directed Enzyme Prodrug Therapy

2005 ◽  
Vol 48 (16) ◽  
pp. 5321-5328 ◽  
Author(s):  
Lawrence C. Davies ◽  
Frank Friedlos ◽  
Douglas Hedley ◽  
Jan Martin ◽  
Lesley M. Ogilvie ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Enzyme Prodrug Therapy ◽  
Carboxypeptidase G2 ◽  
In Vivo Antitumor Activity

Microbial enzymes used in prodrug activation for cancer therapy: Insights and future perspectives

2020 ◽  
Vol 21 ◽  
Author(s):  
Rakhi Dhankhar ◽  
Anubhuti Kawatra ◽  
Aparajita Mohanty ◽  
Pooja Gulati
Keyword(s):  
Purine Nucleoside Phosphorylase ◽  
Cytosine Deaminase ◽  
Therapeutic Index ◽  
Enzyme Prodrug Therapy ◽  
Prodrug Activation ◽  
Microbial Enzymes ◽  
High Productivity ◽  
Delivery Vector ◽  
Exogenous Enzymes ◽  
Activation Therapy

Abstract:: Enzyme prodrug therapy has gained momentum in the recent years due to their ability to improve therapeutic index (benefits versus toxic side-effects) and efficacy of chemotherapy in cancer treatment. Inactive prodrugs used in this system are converted into active anti-cancerous drugs by enzymes, specifically within the tumor cells. This therapy involves three components namely prodrug, enzyme and gene delivery vector. Past reports have clearly indicated that the choice of enzyme used, is the major determinant for the success of this therapy. Generally, enzymes from non-human sources are employed to avoid off-target toxicity. Exogenous enzymes also give a better control to the clinician regarding the calibration of treatment by site-specific initiation. Amongst these exo-enzymes, microbial enzymes are preferred due to their high productivity, stability and ease of manipulation. The present review focuses on the commonly used microbial enzymes particularly cytosine deaminase, nitroreductase, carboxypeptidase, purine nucleoside phosphorylase in prodrug activation therapy. Various aspects viz. source of the enzymes, types of cancer targeted, mode of action and efficacy of the enzyme/prodrug system, efficient vectors used and recent research developments of each of these enzymes are comprehensively elaborated. Further, the results of the clinical trials and various strategies to improve their clinical applicability are also discussed.

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