MEST and hepatocellular carcinoma: While no consistent changes in DNA methylation were observed in MEST, KCNQ1 ICR, and AS-SRO region in HCC tumors and paired surroundings, a significant hypomethylation was detected in HCC in PWS-SRO region (P value <0.005), in agreement with the trend of methylation observed at promoter regions (Figure 2A).