Coupling of a Novel TIMP3 Peptide to Carboxypeptidase G2 for Pro-Drug Activation at the Tumour Site.
Molecules
; 26(3)2021 Jan 25.
Article
en En
| MEDLINE
| ID: mdl-33504102
ABSTRACT
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.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Péptidos
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Profármacos
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Gamma-Glutamil Hidrolasa
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Inhibidor Tisular de Metaloproteinasa-3
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Antineoplásicos
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Molecules
Asunto de la revista:
BIOLOGIA
Año:
2021
Tipo del documento:
Article
País de afiliación:
Arabia Saudita