Abstract
Structurally-related, but non-polyglutamylatable, derivatives of 10-CF3CO-DDACTHF (1), which incorporate L-glutamine (2) and L-isoglutamine (3) in place of L-glutamate, were prepared and evaluated as inhibitors of recombinant human (rh) GAR Tfase. While the L-glutamate alpha-carboxamide derivative 3 was much less effective as a rhGAR Tfase inhibitor (K(i) = 4.8 microM) and inactive in cellular functional assays, the gamma-carboxamide derivative 2 was found to be a potent and selective rhGAR Tfase inhibitor (K(i) = 0.056 microM) being only 4-fold less potent than 1 (K(i) = 0.015 microM). Moreover, 2 was effective in cellular functional assays exhibiting purine sensitive cytotoxic activity (IC50 = 300 nM, CCRF-CEM) only 20-fold less potent than 1 (IC50 = 16 nM), consistent with inhibition of de novo purine biosynthesis via selective inhibition of GAR Tfase. Like 1, 2 is transported into the cell by the reduced folate carrier. Unlike 1, the functional activity of 2 is not dependent upon FPGS polyglutamylation.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, Non-U.S. Gov't
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
Amides / chemistry*
-
Antineoplastic Agents* / chemical synthesis
-
Antineoplastic Agents* / pharmacology
-
Cell Proliferation / drug effects*
-
Drug Screening Assays, Antitumor
-
Enzyme Inhibitors* / chemical synthesis
-
Enzyme Inhibitors* / pharmacology
-
Folic Acid Antagonists / chemical synthesis
-
Folic Acid Antagonists / pharmacology
-
Humans
-
Hydroxymethyl and Formyl Transferases / antagonists & inhibitors
-
Inhibitory Concentration 50
-
Molecular Structure
-
Phosphoribosylaminoimidazolecarboxamide Formyltransferase
-
Phosphoribosylglycinamide Formyltransferase
-
Purines / antagonists & inhibitors
-
Purines / biosynthesis*
-
Structure-Activity Relationship
-
Tetrahydrofolates* / chemical synthesis
-
Tetrahydrofolates* / chemistry
-
Tetrahydrofolates* / pharmacology
-
Tumor Cells, Cultured
Substances
-
10-(trifluoroacetyl)-5,10-dideazaacyclic-5,6,7,8-tetrahydrofolic acid
-
Amides
-
Antineoplastic Agents
-
Enzyme Inhibitors
-
Folic Acid Antagonists
-
Purines
-
Tetrahydrofolates
-
Hydroxymethyl and Formyl Transferases
-
Phosphoribosylglycinamide Formyltransferase
-
Phosphoribosylaminoimidazolecarboxamide Formyltransferase