Hervouet E, Debien E, Campion L, Charbord J, Menanteau J, Vallette FM, Cartron PF. Folate supplementation limits the aggressiveness of glioma via the remethylation of DNA repeats element and genes governing apoptosis and proliferation.
Clin Cancer Res 2009;
15:3519-29. [PMID:
19451595 DOI:
10.1158/1078-0432.ccr-08-2062]
[Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE
We have investigated whether the folate supplementation could be used to limit the aggressiveness of glioma through the DNA remethylation because (a) the cancer genome is characterized by a low level of DNA methylation (or 5-methylcytosine, 5 mC); and (b) folate is the main generator of S-adenosyl-methionine, the methyl donor molecule in the DNA methylation reaction catalyzed by the DNA methyltranferases.
EXPERIMENTAL DESIGN
The effects of folate supplementations were analyzed on the global DNA methylation status, the methylation status of DNA repeat element, the sensitivity of temozolomide-induced apoptosis, and the proliferation index of glioma cells. Finally, we analyzed whether the DNA methylation level could be used as a prognostic factor and/or a biomarker in an antiglioma therapy using folate supplementation as an adjuvant.
RESULTS
Our data show that gliomagenesis is accompanied by a reduction in 5 mC levels and that this low level of 5 mC is a poor prognostic factor in Glioblastoma Multiforme patients. We also show that folate supplementation enhanced the DNA remethylation through the Sp1/Sp3-mediated transcriptional up-regulation of genes coding for Dnmt3a and Dnmt3b proteins, two de novo methyltranferases. Finally, we show that the folate-induced DNA methylation limits proliferation and increases the sensitivity to temozolomide-induced apoptosis in glioma cells through methylation of the genes implicated in these processes (PDGF-B, MGMT, survivin, and bcl-w).
CONCLUSION
This study suggests that folate supplementation could be a promising adjuvant for the future design of antiglioma therapies in preclinical and/or clinical studies.
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