Sodium bisulfite and functional analyses. (a) Sodium bisulfite sequencing of representative genes detected with aberrant methylation and/or associated with epithelial–mesenchymal transition. Each square represents a CpG (open square: unmethylated; closed square: methylated). Each row of squares represents one cloned PCR sequence across the gene promoter (about 20 clones were sequenced per gene). Percentages indicate degree of methylation at each gene locus. (b) Quantitative real-time RT-PCR expression data for each of these genes.