Fig. 4. Pathway enrichment analysis of putative genes correlated with DMPs and expression analysis of genes associated with the neuroactive ligand-receptor interaction pathway.

a Pathway enrichment analysis of hypermethylated genes in GC. The x-axis shows −log (Benjamini test, P), and the y-axis shows the pathway categories. Stars indicate significant pathway categories. b RT-PCR analysis of 16 GC cell lines and ten paired gastric tumor (T) and normal match control (N) tissues. The LOE column indicates the loss of expression as percentages of gene expression upregulation in gastric tumors compared to that in normal tissue. c Restoration test of gene expression in 17 genes in four GC cell lines following treatment with the DNA methylation inhibitor AZA and/or TSA treatment. ROE indicates restoration of expression as a percentage of a GC cell line in which expression was restored