Potent isozyme-selective inhibition of human glutathione S-transferase A1-1 by a novel glutathione S-conjugate Article First Online: 08 August 2005 Received: 05 April 2005 Accepted: 19 May 2005 DOI:
Cite this article as: Cacciatore, I., Caccuri, A., Cocco, A. et al. Amino Acids (2005) 29: 255. doi:10.1007/s00726-005-0232-7 Summary.
Elevated levels of glutathione
S-transferases (GSTs) are among the factors associated with an increased resistance of tumors to a variety of antineoplastic drugs. Hence a major advancement to overcome GST-mediated detoxification of antineoplastic drugs is the development of GST inhibitors. Two such agents have been synthesized and tested on the human Alpha, Mu and Pi GST classes, which are the most representative targets for inhibitor design. The novel fluorescent glutathione S-conjugate L-γ-glutamyl-( S-9-fluorenylmethyl)-L-cysteinyl-glycine ( 4) has been found to be a highly potent inhibitor of human GSTA1-1 in vitro (IC 50=0.11±0.01 μM). The peptide is also able to inhibit GSTP1-1 and GSTM2-2 isoenzymes efficiently. The backbone-modified analog L-γ-(γ-oxa)glutamyl-( S-9-fluorenylmethyl)-L-cysteinyl-glycine ( 6), containing an urethanic junction as isosteric replacement of the γ-glutamyl-cysteine peptide bond, has been developed as γ-glutamyl transpeptidase-resistant mimic of 4 and evaluated in the same inhibition tests. The pseudopeptide 6 was shown to inhibit the GSTA1-1 protein, albeit to a lesser extent than the lead compound, with no effect on the activity of the isoenzymes belonging to the Mu and Pi classes. The comparative loss in biological activity consequent to the isosteric change confirms that the γ-glutamyl moiety plays an important role in modulating the affinity of the ligands addressed to interact with GSH-dependent proteins. The new specific inhibitors may have a potential in counteracting tumor-protective effects depending upon GSTA1-1 activity. Keywords: Glutathione – Glutathione S-transferase inhibitors – Glutathione S-conjugate – γ-Glutamyl transpeptidase – Pseudopeptide References Adang, AE, Brussee, J, Meyer, DJ, Coles, B, Ketterer, B, van der Gen, A, Mulder, GJ 1988 Substrate specificity of rat liver glutathione S-transferase isoenzymes for a series of glutathione analogues, modified at the gamma-glutamyl moiety. Biochem J 255 721 724 PubMed Google Scholar Bodanszky, M, Bednarek, MA 1982 Derivatives of S-9-fluorenylmethyl- L-cysteine. Int J Pept Protein Res 20 434 437 PubMed Google Scholar Bolton, MG, Colvin, OM, Hilton, J 1991 Specificity of isozymes of murine hepatic glutathione S-transferase for the conjugation of glutathione with L-phenylalanine mustard. Cancer Res 51 2410 2415 PubMed Google Scholar Burg, D, Mulder, GJ 2002 Glutathione conjugates and their synthetic derivatives as inhibitors of glutathione-dependent enzymes involved in cancer and drug resistance. Drug Metab Rev 34 821 863 PubMed CrossRef Google Scholar Cacciatore, I, Caccuri, AM, Di Stefano, A, Luisi, G, Nalli, M, Pinnen, F, Ricci, G, Sozio, P 2003 Synthesis and activity of novel glutathione analogues containing an urethane backbone linkage. Il Farmaco 58 787 793 PubMed CrossRef Google Scholar Calcagni, A, Duprè, S, Lucente, G, Luisi, G, Pinnen, F, Rossi, D 1995 Synthesis and activity of the glutathione analogue γ-( L-γ-azaglutamyl)- L-cysteinyl-glycine. Int J Pept Protein Res 46 434 439 PubMed Google Scholar Calcagni, A, Duprè, S, Lucente, G, Luisi, G, Pinnen, F, Rossi, D, Spirito, A 1996 Synthesis and activity of the glutathione analogue γ-( L-γ-oxaglutamyl)- L-cysteinyl-glycine. Arch Pharm Pharm Med Chem 329 498 502 Google Scholar Davies, W, Jr, Ronai, Z, Tew, KD 2001 Cellular thiols and reactive oxygen species in drug-induced apoptosis. J Pharmacol Exp Ther 296 1 6 Google Scholar Dirven, HA, van Ommen, B, van Bladeren, PJ 1994 Involvement of human glutathione S-transferase isoenzymes in the conjugation of cyclophosphamide metabolites with glutathione. Cancer Res 54 6215 6220 PubMed Google Scholar Fotouhi-Ardakani, N, Woo, A, Lewandowska, M, Schecter, R, Batist, G 1998 Identification of the Yc1 glutathione S-transferase mRNA as the overexpressed species in a nitrogen mustard-resistant rat mammary carcinoma cell line. J Biochem Mol Toxicol 12 11 17 PubMed CrossRef Google Scholar Han, G, Tamaki, M, Hruby, VJ 2001 Fast, efficient and selective deprotection of the tert-butoxycarbonyl (Boc) group using HCl/dioxane (4 M). J Peptide Res 58 338 341 Google Scholar Hayes, JD, Flanagan, JU, Jowsey, IR 2005 Glutathione transferases. Annu Rev Pharmacol Toxicol 45 51 88 PubMed CrossRef Google Scholar Koehler, RT, Villar, HO, Bauer, KE, Higgins, DL 1997 Ligand-based protein alignment and isozyme specificity of glutathione S-transferase inhibitors. Proteins: Structure, Function, and Genetics 28 202 216 CrossRef Google Scholar Lang, M, Pelkonen, O 1999 Metabolism of xenobiotics and chemical carcinogenesis. IARC Sc Publ 148 13 22 Google Scholar Lewis, AD, Hickson, ID, Robson, CN, Harris, AL, Hayes, JD, Griffiths, SA, Manson, MM, Hall, AE, Moss, JE, Wolf, CR 1988 Amplification and increased expression of alpha class glutathione S-transferase-encoding genes associated with resistance to nitrogen mustards. Proc Natl Acad Sci USA Cell Biol 85 8511 8515 Google Scholar Lo Bello, M, Battistoni, A, Mazzetti, AP, Board, PG, Muramatsu, M, Federici, G, Ricci, G 1995 Site-directed mutagenesis of human glutathione transferase P1-1. Spectral, kinetic, and structural properties of Cys-47 and Lys-54 mutants. J Biol Chem 270 1249 1253 PubMed CrossRef Google Scholar Luisi, G, Calcagni, A, Pinnen, F 1993 Ψ(SO 2-NH) transition state isosteres of peptides. Synthesis of the glutathione disulfide analogue [γ-Glu-ψ(SO 2-NH)-Cys-Gly] 2. Tetrahedron Lett 34 2391 2392 CrossRef Google Scholar Morel, F, Schulz, WA, Sies, H 1994 Gene structure and regulation of expression of human glutathione S-transferases alpha. Biol Chem Hoppe Seyler 375 641 649 PubMed Google Scholar Morgan, AS, Ciaccio, PJ, Tew, KD, Kauvar, LM 1996 Isozyme-specific glutathione S-transferase inhibitors potenziate drug sensitivity in cultured human tumor cell lines. Cancer Chemother Pharmacol 37 363 370 PubMed CrossRef Google Scholar Oakley, AJ, Lo Bello, M, Battistoni, A, Ricci, G, Rossjohn, J, Villar, HO, Parker, MW 1997 The structures of human glutathione transferase P1-1 in complex with glutathione and various inhibitors at high resolution. J Mol Biol 274 84 100 PubMed CrossRef Google Scholar O’Brien, ML, Tew, KD 1996 Glutathione and related enzymes in multidrug resistance. Eur J Cancer 32 A 967 978 Google Scholar Paglialunga Paradisi, M, Mollica, A, Cacciatore, I, Di Stefano, A, Pinnen, F, Caccuri, AM, Ricci, G, Duprè, S, Spirito, A, Lucente, G 2003 Proline-glutamate chimeras in isopeptides. Synthesis and biological evaluation of conformationally restricted glutathione analogues. Bioorg Med Chem 11 1677 1683 Google Scholar Pompella, A, Visvikis, A, Paolicchi, A, De Tata, V, Casini, AF 2003 The changing faces of glutathione, a cellular protagonist. Biochem Pharmacol 66 1499 1503 PubMed CrossRef Google Scholar Salinas, AE, Wong, MG 1999 Glutathione S-transferases – A Review. Curr Med Chem 6 279 309 PubMed Google Scholar Schultz, M, Dutta, S, Tew, KD 1997 Inhibitors of glutathione S-transferases as therapeutic agents. Adv Drug Deliver Rev 26 91 104 Google Scholar Wilce, MCJ, Parker, MW 1994 Structure and function of glutathione S-transferases. Biochim Biophys Acta 1205 1 18 PubMed Google Scholar Copyright information
© Springer-Verlag/Wien 2005