Figure 1.

Effect of proton beam treatment on global methylation level in the MCF-10A and MCF-7 cell lines. Four CpG sites on the LINE1 in MCF-10A and MCF-7 cell lines were analyzed for their methylation level by pyrosequencing after treatment with a proton beam. (A) The sequence of the LINE1 gene adopted in this study (GenBank accession no. X58075.1). The four analyzed CpG sites are indicated in red and numbered. (B) The methylation level of the CpGs in the two cell lines are shown in bar graphs. Quintuplicated independent samples were analyzed, and average numbers are provided with the associated standard errors. (C) Representative pyrosequencing diagrams for the proton beam-treated and untreated cells.