Effects of antisense-based folypoly-gamma-glutamate synthetase down-regulation on reduced folates and cellular proliferation in CCRF-CEM cells.
The effect of down-regulation of folylpoly-gamma-glutamate synthetase (FPGS) activity on intracellular reduced folate accumulation and cellular proliferation was examined, using an inducible antisense expression system in the human T-lymphoblastic leukemia cell line CCRF-CEM. FPGS catalyzes the addition of gamma-glutamyl residues to natural folates and classical antifolates, which results in their enhanced cellular retention and increased cytotoxicity. As such, this enzyme has become a focus as a potential anticancer drug target. However, direct evidence to support this concept has been elusive. Hence, a study was undertaken using an antisense-based expression system to down-regulate FPGS activity. This inducible expression system was used to demonstrate that lower FPGS activity can lead to substantially lower intracellular folate content, which coincides with suppression of thymidylate synthesis and inhibition of cellular proliferation.
Department of Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston 29425, USA.
Y
Y
Liu
K
K
Raghunathan
C
C
Hill
Y
Y
He
M A
MA
Bunni
J
J
Barredo
D G
DG
Priest
D017931:DNA Primers; D016373:DNA, Antisense; D015536:Down-Regulation; D005492:Folic Acid / Q000235:genetics / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015458:Leukemia, T-Cell / Q000201:enzymology* / Q000235:genetics; D010453:Peptide Synthases / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D014407:Tumor Cells, Cultured / Q000201:enzymology
D017931:DNA Primers; D016373:DNA, Antisense; D005492:Folic Acid; D010453:Peptide Synthases; C023103:folylpolyglutamate synthetase