Fig. 1

Differentially methylated sites between LTS-GBM and STS-GBM. a Heatmap of DNA methylation levels measured as beta values: color gradients from blue to red correspond to beta values from 0 to 1. Hierarchical clustering was performed for both of glioblastoma patients (columns) and the differentially-methylated sites between LTS-GBM and STS-GBM (rows). Here, hierarchical clustering of the most significant sites (−log₁₀(FDR) < 5: 13,049 sites) with Euclidean distance and complete linkage was performed for convenient visualization. b Distribution of the mean increased level of DNA methylation in LTS relative to STS (labelled as “LTS-STS” in y-axis) across the sites categorized by their locations from the closest CpG Island (CGI) (see materials and methods). The group of selected significant sites are denoted by pink while the other sites are described by grey. If the distribution is shifted to the positive in y-axis (for example, at “Island”), it means that LTS has in general higher DNA methylation compared to STS while the shift to the negative in y-axis indicates the opposite case (for example, in “OpenSea”). c Same as (b) except that categorization of sites were done by distances from the nearest transcription start site (TSS) (see materials and methods)