The long term objective of this project is to determine whether inhibitors of the glyoxalase enzyme system, composed of the isomerase glyoxalase I (GlxI) and the thioester hydrolase glyoxalase II (GlxII), can be developed into effective antitumor agents in whole animals. This general strategy is potentially important because (a) it does not directly target nucleic acid metabolism and, therefore, might not give rise to the side effects commonly associated with most cancer chemotherapies, and (b) uses hydrophilic enzyme inhibitors that might be less susceptible to multidrug resistance once delivered into cancer cells as lipophilic prodrugs. In support of the feasibility of this anticancer strategy, we recently synthesized four enediol analogs that are the strongest inhibitors of human GlxI yet reported: GSC(O)N(OH)R, where GS = glutathionyl, R = CH3(l), C6H5(2), C6H4Cl(3), C6H4Br(4). Preliminary in vitro studies are consistent with the idea that these compounds are potential tumor- selective anticancer agents when delivered into human leukemia cells as the lipophilic [glycyl, gamma-glutamyl] diethyl esters. The immediate objective of this revised proposal is to further examine the in vitro and in vivo antitumor properties of these compounds in a murine model system, and to better understand the molecular basis of tight-binding inhibition of GlxI by the enediol analogs.
The specific aims are as follows: (l) To examine the mechanism by which the diethyl esters of the enediol analogs (1-4) are transported into mouse leukemia L1210 cells in vitro. (2) To evaluate the cytotoxicities of the enediol analogs (1-4) and their ethyl esters toward L1210 cells in vitro. (3) To determine the pharmacokinetic properties of the enediol analogs (1-4) and their ethyl esters in serum esterase deficient mice. (4) To test the in vivo efficacy of the enediol analogs and their ethyl esters in serum esterase-deficient mice bearing L1210 murine leukemia and in C.B-l7 SCID mice bearing human tumor xenografts, androgen-independent human prostate cancer (PC-3), and human colon adenocarcinoma (HT-29). (5) To test the hypothesis that stabilization of the enediol(ate) intermediate, formed along the reaction pathway of GlxI, is due to the movement of a flexible (TIM-like) peptide loop near the active site. (6) To test the hypothesis that during the GlxI reaction an active site glutamic acid residue catalyzes the proton transfer associated with isomerization.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA059612-03
Application #
2683538
Study Section
Bio-Organic and Natural Products Chemistry Study Section (BNP)
Program Officer
Lees, Robert G
Project Start
1996-04-02
Project End
2000-03-31
Budget Start
1998-04-01
Budget End
2000-03-31
Support Year
3
Fiscal Year
1998
Total Cost
Indirect Cost
Name
University of Maryland Balt CO Campus
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
City
Baltimore
State
MD
Country
United States
Zip Code
21250
Zheng, Zhe-Bin; Zhu, Guozhang; Tak, Heekyung et al. (2005) N-(2-hydroxypropyl)methacrylamide copolymers of a glutathione (GSH)-activated glyoxalase i inhibitor and DNA alkylating agent: synthesis, reaction kinetics with GSH, and in vitro antitumor activities. Bioconjug Chem 16:598-607
Joseph, Erin; Ganem, Bruce; Eiseman, Julie L et al. (2005) Selective inhibition of MCF-7(piGST) breast tumors using glutathione transferase-derived 2-methylene-cycloalkenones. J Med Chem 48:6549-52
Zheng, Zhe-Bin; Creighton, Donald J (2003) Bivalent transition-state analogue inhibitors of human glyoxalase I. Org Lett 5:4855-8
Creighton, D J; Zheng, Z-B; Holewinski, R et al. (2003) Glyoxalase I inhibitors in cancer chemotherapy. Biochem Soc Trans 31:1378-82
Hamilton, Diana S; Zhang, Xiyun; Ding, Zhebo et al. (2003) Mechanism of the glutathione transferase-catalyzed conversion of antitumor 2-crotonyloxymethyl-2-cycloalkenones to GSH adducts. J Am Chem Soc 125:15049-58
Hamilton, Diana S; Ding, Zhebo; Ganem, Bruce et al. (2002) Glutathionyl transferase catalyzed addition of glutathione to COMC: a new hypothesis for antitumor activity. Org Lett 4:1209-12
Huntley, C F; Hamilton, D S; Creighton, D J et al. (2000) Reaction of COTC with glutathione: structure of the putative glyoxalase I inhibitor. Org Lett 2:3143-4
Kalsi, A; Kavarana, M J; Lu, T et al. (2000) Role of hydrophobic interactions in binding S-(N-aryl/alkyl-N-hydroxycarbamoyl)glutathiones to the active site of the antitumor target enzyme glyoxalase I. J Med Chem 43:3981-6
Sharkey, E M; O'Neill, H B; Kavarana, M J et al. (2000) Pharmacokinetics and antitumor properties in tumor-bearing mice of an enediol analogue inhibitor of glyoxalase I. Cancer Chemother Pharmacol 46:156-66
Kavarana, M J; Kovaleva, E G; Creighton, D J et al. (1999) Mechanism-based competitive inhibitors of glyoxalase I: intracellular delivery, in vitro antitumor activities, and stabilities in human serum and mouse serum. J Med Chem 42:221-8

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