title: Characterization of a fusion protein of RGD4C and the β-lactamase variant for antibody-directed enzyme prodrug therapy.
abstract: Antibody-directed enzyme prodrug therapy (ADEPT) delivers chemotherapeutic agents in high concentration to tumor tissue, while minimizing systemic drug exposure. ADEPT has been reported to be an attractive approach for improving the efficacy of cancer therapy. A previously reported β-lactamase was found to contain four cluster of differentiation (CD)4(+) T cell epitopes; however, single amino acid changes in the enzyme resulted in significantly reduced proliferative responses, while retaining stability and activity of the enzyme. The β-lactamase variant with reduced immunogenicity is an attractive alternative for constructing the ADEPT fusion protein. In this study, we fused the peptide, RGD4C, known to target integrin αvβ3, to the β-lactamase variant for use in ADEPT. Biological function studies revealed that RGD4C-β-lactamase had a high hydrolytic effect on nitrocefin and cephalosporin-melphalan, and high plasma stability was observed. In addition, fusion of the RGD4C moiety to β-lactamase had little effect on immunogenicity compared with β-lactamase in the proliferation of peripheral blood mononuclear cells. The ability of this fusion protein to both target the central region of αvβ3 and induce toxicity in the non-small-cell lung cancer cell NCI-H460 makes it a promising therapeutic approach in the treatment of cancer.
authors.affiliation: Institute of Radiation Medicine, Tianjin Key Laboratory of Molecular Nuclear Medicine, Tianjin, People's Republic of China.
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Institute of Radiation Medicine, Tianjin Key Laboratory of Molecular Nuclear Medicine, Tianjin, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.affiliation: Institute of Radiation Medicine, Tianjin Key Laboratory of Molecular Nuclear Medicine, Tianjin, People's Republic of China.
authors.forename: Peiji
authors.initials: P
authors.lastname: Shi
authors.affiliation: Institute of Radiation Medicine, Tianjin Key Laboratory of Molecular Nuclear Medicine, Tianjin, People's Republic of China.
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Meng
keywords: ADEPT; immunogenicity; integrin αvβ3
references.citation: Biotechnology (N Y). 1995 Mar;13(3):265-70
references.pmid: 9634769
references.citation: Proc Natl Acad Sci U S A. 2007 Mar 27;104(13):5584-9
references.pmid: 17372220
references.citation: Bioconjug Chem. 1998 Mar-Apr;9(2):255-9
references.pmid: 9548542
references.citation: Clin Cancer Res. 2006 Nov 1;12(21):6509-16
references.pmid: 17085666
references.citation: Curr Opin Investig Drugs. 2005 Jun;6(6):611-5
references.pmid: 15997480
references.citation: AAPS J. 2012 Jun;14(2):296-302
references.pmid: 22407289
references.citation: J Immunol Methods. 1976;13(3-4):215-26
references.pmid: 796385
references.citation: Curr Oncol Rep. 2006 Mar;8(2):96-103
references.pmid: 16507218
references.citation: Mini Rev Med Chem. 2010 Sep;10(10):887-904
references.pmid: 20560876
references.citation: Curr Drug Targets. 2009 Feb;10(2):152-7
references.pmid: 19199911
references.citation: Curr Pharm Biotechnol. 2009 Jun;10(4):352-8
references.pmid: 19519410
references.citation: Mol Cancer Ther. 2008 May;7(5):1044-53
references.pmid: 18483294
references.citation: Protein Pept Lett. 2010 Dec;17(12):1562-5
references.pmid: 20858201
references.citation: Pharm Res. 2011 Oct;28(10):2379-85
references.pmid: 21744171