YY1 and neoplasm: We then explored the methylation levels (beta values) of YY1 and PEBP1 across different TCGA tumors and found that PEBP1 is highly methylated in LGG, LAML, LUAD, LUSC, and HNSC, among other tumors, while YY1 is not significantly methylated in any tumor (Figure 4A,B).