Biopolym. Cell. 2013; 29(5):367-374.
http://dx.doi.org/10.7124/bc.00082B
Reviews
MGMT expression: insights into its regulation. 2. Single nucleotide polymorphisms
1Iatsyshyna A. P., 1Pidpala O. V., 1Lukash L. L.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680

Abstract

High intra- and interindividual variations in the expression levels of the human O6-methylguanine-DNA methyltransferase (MGMT) gene have been observed. This DNA repair enzyme can be a cause of resistance of cancer cells to alkylating chemotherapy. It has been studied the association of single nucleotide polymorphisms (SNPs) of MGMT with the risk for different types of cancer, progression-free survival in patients with cancer treated with alkylating chemotherapy, as well as an effect of SNPs on the MGMT gene expression and activity of the enzyme. SNPs have been suggested to be the factors which influence the levels of interindividual variability of the MGMT expression. Therefore, the aim of this paper was to review the experimental data on SNPs of the human MGMT gene, which are associated with cancer, as well as on location of MGMT-SNPs in regulatory and protein-coding regions of the gene in relation to its regulation. Lots of MGMT SNPs, which could affect the gene expression and result in interindividual MGMT variability or the enzyme resistance to pseudosubstrate inhibitors, have been re- vealed within the promoter and enhancer regions, the 5'- and 3'-UTRs and introns of the MGMT gene, as well as within the protein-coding region. Many of them may have regulatory effect.
Keywords: O6-methylguanine-DNA methyltransferase (MGMT), gene regulation, single nucleotide polymorphism (SNP), transcription factor binding site
Full text: (PDF, in English)

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