Epigenetic (5-methyl Cytosine, 5mC) changes in different regions of key genes in oral tongue squamous cell carcinoma. The cover image shows bubble-track images depicting a significant cis-regulatory relationship between gene expression and 5mC DNA methylation for key genes. Blue and orange colors indicate hypo- and hyper-methylations respectively and filled circles indicate a correlation in the expected direction, i.e. hyper-methylation and down-regulation, or hypo-methylation and up-regulation. The sizes of the circles indicate the magnitude of gene expression. For more information, see the article by Krishnan and colleagues beginning on page 805.