Expression of β-glucuronidase on the surface of bacteria enhances activation of glucuronide prodrugs

• Published in: Cancer gene therapy Vol. 20; no. 5; pp. 276 - 281
• Main Authors: Cheng, C-M, Chen, F M, Lu, Y-L, Tzou, S-C, Wang, J-Y, Kao, C-H, Liao, K-W, Cheng, T-C, Chuang, C-H, Chen, B-M, Roffler, S, Cheng, T-L
• Format: Journal Article
• Language: English
• Published: New York Nature Publishing Group US 01.05.2013; Nature Publishing Group
• Subjects: 631/1647/1511; 631/67/1059; Adhesins; Analysis; Aniline; Antitumor agents; Bacteria; Biomedical and Life Sciences; Biomedicine; Carrier Proteins - pharmacokinetics; Colon cancer; Enzymatic activity; Escherichia coli; Escherichia coli - enzymology; Escherichia coli - genetics; Gene Expression; Gene Therapy; Glucuronates - pharmacokinetics; Glucuronidase - biosynthesis; Glucuronidase - genetics; Glucuronidase - metabolism; Glucuronides - pharmacokinetics; Glycosidases; HCT116 Cells; Humans; Hydrolysis; Membrane proteins; Nitrophenols - pharmacokinetics; original-article; Prodrugs; Prodrugs - pharmacokinetics; Tumor Cells, Cultured; autotransporter protein adhesin; surface display; extracellular activation; β-glucuronidase; bacteria-directed enzyme prodrug therapy
• ISSN: 0929-1903; 1476-5500
• DOI: 10.1038/cgt.2013.17

Extracellular activation of hydrophilic glucuronide prodrugs by β-glucuronidase (βG) was examined to increase the therapeutic efficacy of bacteria-directed enzyme prodrug therapy (BDEPT). βG was expressed on the surface of Escherichia coli by fusion to either the bacterial autotransporter protein Adhesin (membrane βG (mβG)/AIDA) or the lipoprotein (lpp) outermembrane protein A (mβG/lpp). Both mβG/AIDA and mβG/lpp were expressed on the bacterial surface, but only mβG/AIDA displayed enzymatic activity. The rate of substrate hydrolysis by mβG/AIDA-BL21cells was 2.6-fold greater than by pβG-BL21 cells, which express periplasmic βG. Human colon cancer HCT116 cells that were incubated with mβG/AIDA-BL21 bacteria were sensitive to a glucuronide prodrug (p-hydroxy aniline mustard β- D -glucuronide, HAMG) with an half maximal inhibitory concentration (IC 50 ) value of 226.53±45.4 μ M , similar to the IC 50 value of the active drug (p-hydroxy aniline mustard, pHAM; 70.6±6.75 μ M ), indicating that mβG/AIDA on BL21 bacteria could rapidly and efficiently convert HAMG to an active anticancer agent. These results suggest that surface display of functional βG on bacteria can enhance the hydrolysis of glucuronide prodrugs and may increase the effectiveness of BDEPT.