Fig. 2

Validation of recurrent methylation changes of 12 genes. a Violin plots of DMR methylation levels of 12 genes in 78 pairs of HCC and non-tumor samples are shown. Differential methylation was tested using Student’s paired t test (***P value <0.001; *P value <0.05). b Distribution of altered DNA methylation of 12 genes between 78 pairs of HCC and non-tumor samples. Four categories of methylation differences between HCC and non-tumor samples are indicated. c Principal component analysis (PCA) of 7 validated genes in 78 pairs of HCC and non-tumor samples. d PCA of 7 validated genes in 78 HCC samples