title: Enzyme specific activation of benzoquinone ansamycin prodrugs using HuCC49DeltaCH2-beta-galactosidase conjugates.
abstract: To activate prodrugs for cancer treatment, an anti-TAG-72 antibody (HuCC49DeltaCH2) was used for delivery of an activation enzyme (beta-galactosidase) to specifically activate a geldanamycin prodrug (17-AG-C2-Gal) against colon cancer. The geldanamycin prodrug 17-AG-C2-Gal was synthesized by coupling a galactose-amine derivative with geldanamycin at the C-17 position. Molecular docking with two different programs (Affinity and Autodock) showed that the prodrug (17-AG-C2-Gal) was unable to bind to Hsp90; however, the product (17-AG-C2), enzymatically cleaved by beta-galactosidase conjugate, bound to Hsp90 in a similar way as geldanamycin and 17-AG. The computational docking results were further confirmed in experimental testing by the tetrazolium [3-(4,5-dimethythiazol-2-yl)]-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay and mass spectrometry. HuCC49DeltaCH2 was chemically conjugated to beta-galactosidase. The antibody-enzyme conjugate was able to target tumor antigen TAG-72 with the well-preserved enzymatic activity to activate 17-AG-C2-Gal prodrug. The released active drug 17-AG-C2 was demonstrated to induce up to 70% AKT degradation and enhance anticancer activity by more than 25-fold compared to the prodrug.
authors.affiliation: Division of Pharmaceutics, College of Pharmacy, Department of Chemistry and Biochemistry, Department of Surgery, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Lanyan
authors.initials: L
authors.lastname: Fang
authors.forename: Robert F
authors.initials: RF
authors.lastname: Battisti
authors.forename: Hao
authors.initials: H
authors.lastname: Cheng
authors.forename: Philip
authors.initials: P
authors.lastname: Reigan
authors.forename: Yan
authors.initials: Y
authors.lastname: Xin
authors.forename: Jie
authors.initials: J
authors.lastname: Shen
authors.forename: David
authors.initials: D
authors.lastname: Ross
authors.forename: Kenneth K
authors.initials: KK
authors.lastname: Chan
authors.forename: Edward W
authors.initials: EW
authors.lastname: Martin
authors.forename: Peng George
authors.initials: PG
authors.lastname: Wang
authors.forename: Duxin
authors.initials: D
authors.lastname: Sun
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry*; D000951:Antigens, Neoplasm / Q000276:immunology*; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology; D016227:Benzoquinones / Q000737:chemistry*; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms; D004337:Drug Carriers; D016503:Drug Delivery Systems; D005697:Galactosides / Q000008:administration & dosage / Q000737:chemistry*; D006023:Glycoproteins / Q000276:immunology*; D018841:HSP90 Heat-Shock Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D007202:Indicators and Reagents; D047029:Lactams, Macrocyclic / Q000008:administration & dosage / Q000737:chemistry*; D013058:Mass Spectrometry; D008958:Models, Molecular; D011355:Prodrugs / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology; D011485:Protein Binding; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D013778:Tetrazolium Salts; D013844:Thiazoles; D001616:beta-Galactosidase / Q000737:chemistry*
chemical_list: C515135:17-amino-17-demethoxygeldanamycin -C2-galactose; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D016227:Benzoquinones; D004337:Drug Carriers; D005697:Galactosides; D006023:Glycoproteins; D018841:HSP90 Heat-Shock Proteins; D007202:Indicators and Reagents; D047029:Lactams, Macrocyclic; D011355:Prodrugs; D013778:Tetrazolium Salts; D013844:Thiazoles; C047052:tumor-associated antigen 72; C070380:3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium; D051057:Proto-Oncogene Proteins c-akt; D001616:beta-Galactosidase; C515136:17-aminogeldanamycin; C001277:geldanamycin