Hypermethylation of CpG dinucleotides at the 5′ transcriptional regulatory region has been shown to be sufficient to inhibit GSTP1 transcription in the MCF-7 breast cancer cell line when mediated by the methyl-CpG-binding domain (MBD) protein MBD2 (Lin and Nelson, 2003). This evidence concerns the gene GSTP1 and breast carcinoma.